The
press release for the mile-based exit numbers around Syracuse has a link to a PDF with a table of the old/new numbers around Region 3 (it's right before the politicians start sharing their thoughts). Posts on the AARoads forum note that the conversion has begun, with old exits 9 and 10 on I-81 already changed.
The thing is, this is going to be messy. The exits outside of the construction area for all the various projects associated with I-81 are set to change this year. That's I-81 exits 9-16 and 30-37, I-690 exits 1-8, and NY 481. I-81 in Regions 7 (exits 38-52) and 9 (exits 1-8) are TBD. The remainder will convert as the signs are replaced as part of the I-81 projects. This will result in duplicate numbers for 38/39, 50, and 52 on I-81 for an indeterminate length of time.