May it be seen as it was intended and not otherwise:
Counting that there is still hope (for also formal, Nibbana isn't a topic an always sure for those practicing straight the path), Bhante pointed out a valid possibility traced way such could arise, in one of his essays:
"If there would be five 'perfect' Bhikkhus, who would undergo a spontaneous sex-change, then there would be a remaining valid Bhikkhuni-Sangha."
May all be able to join the merits conducted by this wish, and may the Devas inform those not touched yet.