It's going to be rough.
I had a trip towards the beginning of the year, started planning it closer to 100 days out. Getting some FPs and ADRs (especially at times we needed) was tough, but at the end we ended up getting everything at exactly the time we needed by checking multiple times a day. Everything but BBB that is.
The problem with BBB is that you can't book it yourself, you need to call the reservation line. So what should take 30 seconds online takes 5+ minutes by phone, if lines aren't busy. We eventually got a late (4:30pm) reservation at DTD after trying for a while, but no matter how hard we tried nothing else opened up, including the days leading up to the reservation, for either MK or DTD.
They need to try ASAP and keep calling daily for cancellations if they really want it, plus be prepared to only get a late res at DTD. It was my first try at BBB, but from what I read my experience was somewhat common.