Three months or roughly twelve weeks from what I have read seemed to be about the minimum time to implement another referendum or a PV.
The EU seems to have dug in its heels, May has seemed to dug in her heels, the opposition to May seems to have dug in its heels. For a radical change to occur there would have to been momentum to have built up to this point and that just isn't there.
The EU has already made preparations for a no-deal or is busy wrapping up those preparations. People are moving from the U.K. or are busy making plans to leave. May has seemingly rejected for now anyway a trade deal with the U.S. because she didn't like the food standards of the U.S. and has also rejected an offer from India because of the visa issue.
The U.K. government appears to have been waiting for the past two years for the EU, the U.S., India, etc to come begging for a trade deal solely on whatever terms the U.K. wished once the U.K. leaves the EU.
These things have not happened.
With the start of the new year it does dawn on one just how short three months really is and barring a miracle or two it is basically game over.
One can only then wish the U.K. good luck with whatever the final outcome.