While I understand your conservative times, if, and that’s a big if, no RFI, then there is no rule saying the MHRA has to wait 70 days. Given they would not need to review a response to an RFI in that situation, the deliberation is much much shorter than it would otherwise be, which might mean a great deal shorter than 70 days.
That said, we do not know if there was no RFI.