Was explaining Lineage to another martial artist the other day and came up with a theoretical situation I couldn't answer.

I know that your Lineage is that of the Black Belt who gave you your last grade so if you are a creonte your lineage can 'change' if you switch clubs and receive a new belt

So if X goes through all their grades with a particular instructor/team but then after receiving their Black belt they change their affliation to a new team/instructor with a different lineage, some time after this Y starts training BJJ with X when Y gets their first grade from X what will Y's lineage be??

X's lineage from their old team or their new team??

Yes a very geeky question I know (and completely ignoring the should they be changing teams at black belt etc etc) Thank you in advance!