Thank you very much @pvarley
Through the ticket that we opened with the Enterprise Support we have collaborated with your coworker Matt in the diagnosis of the bug and at all times we have been correctly informed.
Besides being solved in 6.5.0 thanks to the refactor, we have also been informed that a fix will be released in 6.0.4 
Due to stability issues and not to force a new rebalancing for the upgrade, we will stay in 6.0.3 and as workaroung we will keep the TTL of the buckets in 29 days
Thank you