Scheduled removal of the SC-B- engine clusters; they should be replaced effectively by the general engine clusters

which engines are those (SC-B-ENG 2/3/4/5), I can't find them, or do you mean all engine clusters in general?

they were the old pre-built SLS engine clusters with RS-25 engine bells only.

All of the new single engines, and engine clusters in the engine cluster tab, will be staying around for the foreseeable future.