Trump is in control of the MILITARY
Control was attempted to be transferred per protocol, but protocol requires that the request is made on the executive side and granted on the military side.
There is an extremely detailed MILREG on how it is to be done, and the steps necessary to transfer operational control of the military. If there is any question of the mental competency of the incoming administration, the JCOS, by majority vote can defer or reject the request.
Mental competency is only one parameter...legitimacy of the civil election is another. Similar to temporary authority granted by most legislatures to state governors, JCOS can defer in 30 day increments thus avoiding a constitutional crisis.
That has been what is going on, in 30 day increments.
By Trump's order, the imposter in chief and his mindless lackey were refused transport on AF1 and AF2. They resorted to green screen subterfuge long enough to dry lease and mimic paint up some surplus Boeings with AF1 livery, but there is nothing inside except bare accommodations.
On July 20th, the six months of aggregate deferment will be used up...and the JCOS will formally reject the transfer to the imposter in chief and military control will revert to the rightful President. The USSC will confirm and the Biden Administration arrested.