Gnomish and Goblin engineering

Remind me. If I unlearn one of these after learning all the schematics, will that unlearn the schematics or can I just end up learning both and keeping both?

I think you unlearn the recipes associated with switching your specialization.

…or you retain them, but can’t craft them.

I believe the former is more likely. I don’t know of a way to test this though nor have I found a guide online with the answer. Sorry friend.

I’m pretty sure you lose everything when you switch, similar to when you switch professions