Thanks for the information.
When was this change applied? Was it announced in patch notes?
I've been reading patch notes to keep me up to date (even when I was on a break from the game) and this would be something I would've noticed - since it's a potential loss-of-ship change.
There is a mention of "Fixed 3 potential exploits thanks to @qw569 research" in patch 33, but if that was all there was of information I still feel I have a case for a ship refund. I played according to the established gameplay mechanics, without being informed of the mechanics being changed.
PS. I never used this as an exploit, I actually wanted to kill the NPC properly myself for the Patrol damage.