An extension and a new negotiation with new/no 'red lines'. Presumably May is finally toast. tbh the only thing I would totally rule out as a possible eventual outcome is 'no deal'.
Not sure I'd be ruling anything out or in. Even the vote to rule out no deal won't stop it from happening if the blundering continues.
May has to go is the only route out of this I can see. With her gone then extension to A50 may have some purpose but it serves no purpose if May is still there pushing her boulder up hill for all eternity.