Apparently no-one else asked this (or my search attempt failed)... Anyway, everything started when I was registering myself on the Android SE site using the same email that I used in the other accounts.
Associating the account went good as usual except for something weird. It did associate my account since I received the +100 rep bonus but the rest is not synced. For example:
- My username there is not Alenanno, rather user20843.
- The profile is empty (not synced).
Is there something wrong here? It looks like a bug to me, so I tagged it accordingly but who knows.