Without speaking for Chase (I worked for a number of large banks but Chase wasn't one) but having run into the same thing on my mortgage, what they're actually saying is the 4/1 payment should go to Chase. Given that you already have the new servicing information, they already have the back end to accept payments. You wouldn't, however, make the 3/1 payment to Chase.
And while I never advise any of my members to do it, a payment made before the 15th wouldn't be considered delinquent, yes.
Awesome, thank you. Then I'll just make the first payment on the 1st of April just to be sure. Then maybe set up recurring automated payments for the end of the month or something.