Well this is definitely weird.
I would recommend opening a PMR: How to ask for IBM product help: PMRs, RFEs, and more
I would provide a link to this post in the PMR as well as much info as you can about the issue.
I’d be curious if rebooting the root would do anything.
Were any updates applied recently?
How far off was the number of bes computers ? Was it 100’s? 1000’s?