For tax year 2018, couple filed an extension for MFJ return.  Consequently, they ended up filing separately, and the spouse got a  letter about not filing an extension.  It was cleared up after submitting explanations, copies, etc.

It looks like they might file separately again this year, but it is not a certainty.

I'd like to be proactive and file a joint extension and also a separate extension for each.  Is it permissible to do this?  If yes, will the program let me e-file 3 extensions or should I go via USPS?