Amethyst will start automatically updating relays that are sending old versions of replaceables or events that have been deleted. 

This will help fix many race conditions and simply get rid of old information out there. Some pubkeys have 40 different metadata versions in separate relays. 

If your relays start to receive many insertions with dates in the past related to a batch of events the relay just sent out, that's why. 

Consider removing rate limits for deletions and updates of older replaceables the relay already has. You can put those in a slower processing queue, but they should be processed and not just discarded.