[Client] Swapping between servers

I play on both the NA and LAN servers regularly. Prior to this patch it would only take a couple minutes usually displaying 0% and jumping straight to 100%, holding a minute before finishing, but now appears to be re-downloading/repatching something every time.

1. Client on NA, click to swap to LAN.
2. Watch it appear to download as if patching.
3. Once that's complete, click to swap back to the NA server.
4. Watch it appear to download again as if patching.

It happens every time I swap servers, regardless of whether it's starting on NA or starting on LAN.