I would have thought that they would just have the one user ID, eg ("1630982" ) regardless how many times they change their name
AW don't keep track of them though (or at least they can't be bothered). It would be helpful if they showed us "aliases" like they do for punters though - so if they wanted to link them to old profiles they could easily do it or they could do it via their verification process (but either way it's not in their interests). As such, if a WG creates a totally new account they get a new user ID but obviously don't have any of the feedback they used to have etc.
If they just change their username then their ID number stays the same but that 2nd link (
External Link/Members Only) will change (and the original one won't work anymore).
One tip when searching for info on here is to search for both links as sometimes, very occasionally, people only post the 2nd link.