This is logically impossible. First, there is NO Qanon; there is Q and a flock of anons that dissect and decipher Q's posts and generate their own theories, some of them gratifying fantasies.
Second, I doubt Q ever posted that Trump will re-obtain the WH on March 4. Again, I suspect some bright ambitious anon cyphered this out of some other anon's Q-speculation. Q's drops are posted on the web in numerous places - available to any 'journalist' or investigator truly in search of the truth.
This just smacks of official malarkey designed to justify some questionable policy decision-making - like keeping citizens away from their own government buildings and representatives for an extended period of time with a tall razor wire fence and military troops.