I'm continuing to have the problem of my 620 duplicating wifi networks in my watch, resulting in not being able to sync by wifi. That's a known issue and I know how to deal with it - by deleting the networks in Express - except that Express isn't deleting them any more.
I know this for sure because there are networks I haven't used in months that are still appearing (several iterations) in my 620, even after supposedly deleting them in Express and *not* re-entering them.