There is no errata/faq that I know of for Spring 1942.
It can be found here.
In case Krieghund comes in on this, here’s a question - what happens if the attacker couldn’t retreat to a legal adjacent sea zone? That is, suppose UK built a cruiser and two transports in the sea zone between London and Paris on UK’s turn. Then suppose Germany moved some subs to that sea zone on Germany’s turn (but submerged), then UK picked up and dropped off from London to Paris. In that case, UK attacked, but didn’t move attacking units, so then the attacker couldn’t “retreat to an adjacent sea zone that one of the attackers had come from” because the attackers didn’t move at all. Would that mean UK could NOT retreat in such a case?
Yes, that’s what it means. However, in this case UK could simply ignore the subs and would have no reason to retreat.
In genken’s scenario, if the UK fleet could not retreat the battle would end once the attacker was reduced to only planes and the defender to only subs, and the transports would be automatically destroyed.