We have run into a problem with Collector using a web map that has multiple instances of the same feature - each layer a different subtype and then symbolized by a status for that feature within the subtype (e.g. subtype A status 1,2,3; subtype B status 1,2,3, etc.). When a user edits a feature and that causes the feature to a) have a different status or b) change the subtype and then saves; if they go back and edit an additional attribute for that same feature (e.g. comments) a new feature is created resulting in duplicates of the same feature instead of just an updated feature.
We are able to see the new feature is created as a result because we track creation user and ID, and it appears when this process happens.
This has only been repeatable on iOS. We are running iOS 13.2 (17B84) with Collector 19.2.0. It does not occur using Android