Not true. The March 19th deadline was used to determine dealer allocation numbers. Since then, Ford has now sad that they're going to be building Broncos whether they match orders or not and sending them to dealers to fulfill their allocation.If your order was not in by March 19th or whatever it will not be considered until 2022.
So your place in line does matter, but your build spec can get you a Bronco sooner regardless of that old March deadline.
Right now the only deadline that matters is July 16th for soft top scheduling.