i just recently combined some OKW and BWV points to book 1 night at BWV once i was past the 7mo window.
MS did not say a thing to me about transferring points between the contracts.
(i didn't expect them to mention it. btw, i have the same main contract#, just different add-on sub-contract suffixes)
anyway, out of curiosity, i got a copy of my Points Activity Sheet from MS.
i had assumed that MS would do a transfer of the OKW points to my BWV contract behind the scenes to book this 1 night at BWV.
however, after deciphering the Points Activity Sheet, i see they did not do that... instead they deducted a bunch of points from my OKW contract, and a bunch of points from my BWV contract... both referencing the same ressie#.
there is absolutely no record of any transferring between accounts.
so, it looks like MS doesn't even need to transfer points around in this case.
they just seamlessly combined the points.
(unless there is some other even more behind the scenes Points Activity Sheet where they record the transfer?? )
anyway, hope this helps.