I wouldn't get my hopes up over it. Likely be a reprint. IDW could of made a spooky-special for 2019 Halloween ComicFest. This was during the Metal Virus arc.
Hm, a current ongoing story arc involving a zombie-likle plague, zombies being traditional with Halloween and an oppotunity for a Halloween special ... I GOT NUTHIN'! REPRINT ISSUE #1!
The synopsis is out as follows:
Sonic’s racing into a brand-new adventure with his best buds (and co-stars of the hit new movie) Tails and Knuckles by his side!
But Sonic’s not the only super-speedster in town…
Get caught up with everything you need to know about Sonic’s evil counterpart Surge before she and Sonic go head-to-head in the epic issue #50, a story years in the making!
Guess it's a prelude story leading into issue #50.