Interrupting base construction ship after escape

[Aquitaine]

Not sure if this is a bug or WAD but it's inconsistent.

I have a new colony. I send a construction ship to build a big 'ol monitoring station/defense base over it. It takes a while. That's fine.

50% of the way through, pirates attack and the construction ship moves off to escape. I can no longer finish construction with the construction ship - if I select the ship and then target the base, I can move there, patrol it, etc. but no option to repair it comes up. I must now finish building it from the planet which takes forever.

Either I should not be able to build a base with a construction ship to begin with, or I should be able to resume building it after it is interrupted.