Yes, do come back, Nan! Your Welsh was lovely on bootcamp, and I'm pretty certain that most of that will still be there!
I'm interested to know - does sign language sit in the smae part of the brain as other languages. Most people will find that when they learn a new 2nd language, it supersedes their first second language (if you see what I mean). So Cat, when trying to speak French, will come out with a complete Welsh sentence and be sure that it is French, because her Welsh has taken over. Her French is still there, though, so she still understands better than me!
But how would that work with sign language? It would be fascinating to know whether your first thoughts as you try to think of Welsh, are of the signs and less complicated grammar of sign language, and how that manifests itself as you practise. Could you let us know?