Sorry your traveling partners can't join you.
A studio would have to become available before your waitlist could work. MS will not find someone who has a studio but wants a 2 bedroom and then arrange a swap. (There are too many members and the waitlists too complicated for anything like that to be feasible). Since you only want BCV, the chances of something working out for you are small.
To avoid having the extra points go into the holding account, the waitlist needs to work for you befroe the 31 day mark. (So you can cancel the 2 bedroom and re book the studio at least 31 days ahead of time). If it were me, I'd call MS at the 32 or 33 day mark - members who are thinking of cancelling will do so around that time to avoid the holding acount. (As you probably know, there are restrictions on how you may use holding account points and they will expire at the end of your use year if not used. Can't bank or borrow them, either).
If you are willing to take a chance on being able to use holding points for your February trip (or the Manhattan trip), tell MS you want to stay on the waitlist after the 31 day mark. Then if nothing comes through by the 7 day mark, call daily to see if something has come open. (You have to request to stay on the waitlsit after the 31 day mark - most don't want to, and there are no waitlists at all after the 7 day mark).
If something works out after the 31 day mark, you may be able to use the holding account points for one of your other trips. If you want more info on the holding account reservation restrictions and/or the 60 day rule (which would apply to the Manhattan trip), post again.
Hope it works out for you -