Well, we know OTCM's come up with many new fees in recent years. Once upon a time OTCQB companies paid no fee at all. Now they have to cough up $10K annually.
Perhaps once the OTCBB finally bit the dust--okay, it isn't quite dead, but very close to it--OTCM decided it could start charging the MMs, since OTCBB was no longer a competitor for their business.