This is SE-network-wide behavior. It has been brought up on MSE and is by design. The answer to why is "performance reasons" (specifically, to deal with a denial of service attack):
Requests from anonymous users to some of these routes were causing an unacceptably large performance hit a few days ago, potentially hurting the experience for many other ...
That question would have gotten closed on Stack Overflow.
It is a bad question - OP is asking people to do his work for him and would have gotten shot down rather quickly.
That is orthogonal to your question though - there are up to 5 slots for migration on every Stack Exchange site - sites still in beta only have a migration path to their child-meta (for ...
This is by-design. From the SE meta:
The review indicator in the top-bar is not calculated on a per-user basis, but on a per-site basis. The counts in the review queue itself are calculated on a per-user basis.
So, when there are reviews that you've already acted on but still need action from more users, they'll still show in the indicator bar.