We're running an internal migration of all old players' stats to our new highly advanced statistics tracking backend. This means that stat changes will be a bit delayed while we ingest this huge backlog of data. Nothing is being lost, it'll just take a bit longer to show up in the in-game UIs.
Read the last post of this thread (relating to opening separate servers for 1.8 and 1.9).
If your original thread was locked, there is always a reason for it.