Another good indicator of bulletin moving more regularly would be if they move the filing date because that hasn't moved either in a long time. My medicals are going to expire in August and it would be really annoying to have to pay again for an updated medical.
December Bulletin out and no movement.
The most annoying fact is according to Charlie there will be an estimated 10,000-15,000 unused family visa numbers for fiscal year 2024.
I would make it clear at the interview that she would like to remain as an F2B. I don't think a letter in addition is necessary, but at the same time it probably wouldn't hurt.