D.C. embassy said tell customs you will be driving when you leave and first couple of times just cross for a day and come back so they get 2 know u
A verbal statement w/o any type of fare seems counter productive.
Get a cheap Belize Air with open date to Cancun strikes me as a safer bet.
Don't ask Belize embassy about customs questions because they will tell you ask customs.
I arrive 4/2 Belize City Goldson and obviously need a proper work around for ongoing requirement