In Authoritative Shards (FCV 9.0) we assume the shard always has correct metadata, both durable (shard.catalog.collections) and in-memory (the CSR/DSR).

During the FCV 8.x -> 9.0 upgrade however, we are deliberately not clearing entries on the CSR nor the DSR since we assume that the 8.0 state is a valid 9.0 state.

In practice this can become problematic in the same case as SERVER-132477: In the "initializeAutoGet" optimization, we can try to route using a TRACKED shardVersion against an authoritative shard that still says UNTRACKED, due to this bug, this will never converge (we will assume the UNTRACKED is the truth so no refresh is needed) and raise a StaleConfig.