Any mapping rules updates require all existing bib/authority records to be touched to apply these updates. This is current a very slow and manual process; e.g. the process can run for weeks
The new module can run in simultaneuosly tracks. 100.000 records was in preliminary test run in 5-10 minutes. If increasing the resources you can achieve a faster mapping. See more here. Inconsistens or optimistic locking errors are stored in logfiles; but not in the data base. Technical and Design specifications, see here. This does not impact linking between bibs and authority records.
Support tenant level MARC validation. Ramsons requirements. The quickMARC UI has been updated to throw warning when editing. This check is happening in the API. But not preventing the record to be stored, unless it is errors. This work do apply to ECS too.