I can't get that 17c/34 puffer (but no spaceship!) out of my mind.
I had dreamed of trying to find a strict p2 c/2 spaceship that could survive a collision with a piece of debris and recover, either deleting the debris or changing it but thought my best ideas for searching it were too much of a long shot. This recent c/4 back glider eater made me a little more optimistic and I went and sketched something.
I picked 8c/16 s2s more or less randomly and wrote a huge and complicated constraint file:
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| BAHGFEDCBAuuuuuuuuuuuuuRRRRRRRR | BAHGFEDCBAuuuuuuuuuuuuuRRRRRRRR | BAHGFEDCBAuuuuuuuuuuuuuRRRRRRRR | BAHGFEDCBAuuuuuuuuuuuuuRRRRRRRR | BAHGFEDCBAuuuuuuuuuuuuuRRRRRRRR | BAHGFEDCBAuuuuuuuuuuuuuRRRRRRRR | BAHGFEDCBAuuuuuuuuuuuuuRRRRRRRR | BAHGFEDCBAuuuuuuuuuuuuuRRRRRRRR | BAHGFEDCBAuuuuuuuuuuuuuRRRRRRRR | BAHGFEDCBAuuuuuuuuuuuuuRRRRRRRR | BAHGFEDCBAuuuuuuuuuuuuuRRRRRRRR | BAHGFEDCBAuuuuuuuuuuuuuRRRRRRRR | BAHGFEDCBAuuuuuuuuuuuuuRRRRRRRR | BAHGFEDCBAuuuuuuuuuuuuuRRRRRRRR | BAHGFEDCBAuuuuuuuuuuuuuRRRRRRRR | BAHGFEDCBAuuuuuuuuuuuuuRRRRRRRR |
| ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... |
| ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... |
| ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ...........WWWWWWWWWWWW........ |
| ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............WWWWWWWWWW......... | ..........WWWWWWWWWWWWW........ |
| ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............................... | ............WWWWWWWW........... | ...........WWWWWWWWWWW......... | ..........WWWWWWWWWWWWW........ |
| *......**...................... | *......**...................... | **......**..................... | **......**..................... | .**......**.................... | .**......**.................... | ..**......**................... | ..**......**................... | ...**......**.................. | ...**......**.................. | ....**......**................. | ....**......**................. | .....**......WWWWWW............ | .....**....WWWWWWWWW........... | ......**...WWWWWWWWWWW......... | ......**..WWWWWWWWWWWWW........ |
| .*....*..*..................... | .*....*..*..................... | ..*....*..*.................... | ..*....*..*.................... | *..*....*..*................... | *..*....*..*................... | .*..*....*..*.................. | .*..*....*..*.................. | ..*..*....*..*................. | ..*..*....*..*................. | ...*..*....*..*................ | ...*..*....*.WWWW.............. | ....*..*....WWWWWWW............ | ....*..*...WWWWWWWWW........... | *....*..*..WWWWWWWWWWW......... | *....*..*.WWWWWWWWWWWWW........ |
| *......**.......HHHHHHHHHHHHHHH | *......**......HHHHHHHHHHHHHHHH | **......**......HHHHHHHHHHHHHHH | **......**.....HHHHHHHHHHHHHHHH | .**......**.....HHHHHHHHHHHHHHH | .**......**....HHHHHHHHHHHHHHHH | ..**......**....HHHHHHHHHHHHHHH | ..**......**...HHHHHHHHHHHHHHHH | ...**......**...HHHHHHHHHHHHHHH | ...**......**..HHHHHHHHHHHHHHHH | ....**......**WWHHHHHHHHHHHHHHH | ....**......WWWWWHHHHHHHHHHHHHH | .....**.....WWWWWWWHHHHHHHHHHHH | .....**....WWWWWWWWWHHHHHHHHHHH | ......**...WWWWWWWWWWWHHHHHHHHH | ......**..WWWWWWWWWWWWWHHHHHHHH |
| ...............HHHHHHHHHHHHHHHH | ..............HHHHHHHHHHHHHHHHH | ...............HHHHHHHHHHHHHHHH | ..............HHHHHHHHHHHHHHHHH | ...............HHHHHHHHHHHHHHHH | ..............HHHHHHHHHHHHHHHHH | ...............HHHHHHHHHHHHHHHH | ..............HHHHHHHHHHHHHHHHH | ...............HHHHHHHHHHHHHHHH | ..............HHHHHHHHHHHHHHHHH | .............WWHHHHHHHHHHHHHHHH | ............WWWWWHHHHHHHHHHHHHH | ............WWWWWWWHHHHHHHHHHHH | ...........WWWWWWWWWHHHHHHHHHHH | ...........WWWWWWWWWWWHHHHHHHHH | ..........WWWWWWWWWWWWWHHHHHHHH |
| ..............HHHHHHHHHHHHHHHHH | .............HHHHHHHHHHHHHHHHHH | ..............HHHHHHHHHHHHHHHHH | .............HHHHHHHHHHHHHHHHHH | ..............HHHHHHHHHHHHHHHHH | .............HHHHHHHHHHHHHHHHHH | ..............HHHHHHHHHHHHHHHHH | .............HHHHHHHHHHHHHHHHHH | ..............HHHHHHHHHHHHHHHHH | .............HHHHHHHHHHHHHHHHHH | ..............HHHHHHHHHHHHHHHHH | ............WWWWHHHHHHHHHHHHHHH | ............WWWWWWWHHHHHHHHHHHH | ...........WWWWWWWWWHHHHHHHHHHH | ...........WWWWWWWWWWWHHHHHHHHH | ..........WWWWWWWWWWWWWHHHHHHHH |
| HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHWWWWWWHHHHHHHHHHHHH | HHHHHHHHHHHWWWWWWWWWHHHHHHHHHHH | HHHHHHHHHHHWWWWWWWWWWWHHHHHHHHH | HHHHHHHHHHWWWWWWWWWWWWWHHHHHHHH |
| HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHWWWWWWWWHHHHHHHHHHHH | HHHHHHHHHHHWWWWWWWWWWWHHHHHHHHH | HHHHHHHHHHWWWWWWWWWWWWWHHHHHHHH |
| HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHWWWWWWWWWWHHHHHHHHHH | HHHHHHHHHHWWWWWWWWWWWWWHHHHHHHH |
| HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHWWWWWWWWWWWWHHHHHHHHH |
| HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH |
| HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH |
| HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH | HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH |
Here's what's going on in it:
Gens 0-9: A giant envelope of H's (which are forced to be strict p2 c/2) march westward towards a line of hives spaced 8 apart.
Gen 10: The first unknown cells happen when there are neighborhoods from the previous generation whose future is not ordained by CA rules or by the pre-existing c/2 bits. These are represented by four W's, or arbitrary cell wildcards.
Gen 11-15: The hives continue to sit and the H's continue to march, but the uncertain W's expand outward at the speed of light.
Gen 16: Doesn't exist, at this point it has wrapped around and whatever was done has to have killed the hive and repaired the ship.
This constraint file is strictly unsolvable, even at arbitrary width, but I believe the principle works and the partials look like what you'd expect, sort of. You get a c/2 ship moving west, it collides, some madness happens and the hive dies and somehow the c/2 ship recovers. Unfortunately the partials look like they're relying on a lot of help from "off screen" (below how far the partial has extended) and as I said, they cannot be completed.
I sketched the next constraint in this pattern (gen 09 having the first W's, giving it one more generation to finish the interaction) but could not complete the arbitrary width search due to memory constraints. I ran some searches with more limited amounts of 8c/16 cells but none of the partials from any search look very good to me and I'm unsure what sort of alterations to the constraints to try to make to continue pushing on this project. Maybe reduce how far south the W's are allowed to go? It seems unlikely that the non-c/2 perturbation would travel that far into the c/2 ship and somehow still end up eventually corrected. I think the partials are relying on help from the south that they can't really get and so maybe if I cut the W's off the search would be able to rule stuff out sooner. I gotta think about it...