Of the 400 Australopithecus mentions, 200+ are on LWOP. Many won't return at all and others won't return for at least another 5+ years.
Some of the other 200 mentioned have been 'parked' on the 737 where hours are low but provide a significant surge capacity if things improve.
I'd suggest that the current over capacity of crew currently still in uniform flying for mainline is closer to 60- perhaps a few less. The issue remains still that people are in the wrong categories. Over stocked in some categories and under stocked in others. I wouldn't rule out further RINs although that depends a little on potential aircraft orders.