chunkVersion >= collectionVersion

Hello,
we upgraded our sharded cluster from MongoDB 4.4.4 to MongoDB 4.4.9
And while data nodes are working, config and mongos nodes are constantly crashing with

{"t":{"$date":"2021-10-06T12:09:39.676+00:00"},"s":"F", "c":"-", "id":23079, "ctx":"ConfigServerCatalogCacheLoader-0","msg":"Invariant failure","attr":{"expr":"chunkVersion >= collectionVersion","file":"src/mongo/s/chunk_manager.cpp","line":614}}

Idea is that balancing was happening during the upgrade and that lead to this issue.

Is there a nicer fix for this problem, cause currently we are downgrading back to 4.4.4 and will allow to rebalance properly and stop balancing properly now.

Also, any reason why chunkVersion is higher or equal, I would expect it to be lower than collection version, if it is a version mismatch

Any information would help :slight_smile:

Unfortunately, downgrading did not help
so any help or ideas are appreciated