Your broker may require you use a limit order when buying OTC BB stocks. If so, set the limit a few cents above the current ask price. Be careful if you select the All or None option, because this will not fill if shares are not immediately available. Also, you could consider using the option of letting your offer ride Until Cancelled. That way you could get partial fills for several days from the same order.
If NJM' s theory about the 6-month fuse expiring on Feb 27 (tomorrow) is correct, shares can indeed get scarcer. B/c there are no more vendor financing shares floating around, only retail shares.