Confirmation would really mean digging through all the AI scripts, which I don't think anyone has done, but there are anecdotal reports of it happening. E.G. plane flies past acting blind, but it's not enganging because it has no guns, but a while later a few DDs show up.
I have seen convoys move away from me when an escorting DD has spotted me - was quite amazing and very annoying
. They all turned so that intead of being ahead and to the side, I was astern of the convoy. Really ruined my day. So the behaviour is there, but I'm not 100% sure that the planes can do it, but it would make sense that they can.