To open a bank account you need to get a Non-O retirement Visa, do that for your April arrival and you'll get a 90 day entry stamp to get things set up. You can get a marriage Non-O further down the line or swap from a retirement Extension of Stay to a marriage Extension of Stay in the future.
People have reported having issues getting a second Visa Exempt entry, there is no number or threshold that can't be exceeded, it's always a risk as entry is at the discretion of the Immigration Officer