Right now, it would seem that Hoffman's chances of winning with the absentee ballots are slim and none. Trailing by 3,000 votes with 10,000 absentees to be counted, he would need a 30 point plurality in those ballots. Generally speaking, the the absentee ballots break fairly close percentagewise as compared to the other votes. So a 30 point margin would be too much to expect.
Hoffman does have every right to be teed off at the miscounting errors that were supposedly corrected, and to "unconcede." But his "unconceding" is merely a ceremonial protest.
Hoffman should be preparing ASAP for a Republican primary campaign for the same seat next year.