I believe I see the eBay post you're talking about. Looks like a good deal!
Some things to note: the pictures show a bike with a 2x drivetrain (front shifter, crankset with two chainrings), but the text description specifies a 1x bike (and matches the current bike description from the surly website). Before buying I would contact that seller and get clarification what exact bike he's selling. Also, the pictures look like stock pictures scraped from the web, not ones of the bike itself (which may be in a box partially disassembled)
Assuming the text that matches the surly website is correct, I think that's preferable to have a 1x drivetrain. Simpler.
But it's possible the seller's pictures are accurate, it might be that Surly recently released a new version of the Wednesday, and he's trying to clear out his old stock, but he pasted whatever was on the surly website, which describes the latest model.
Older model for that price is not necessarily bad, but I'd want to at least get a look at the actual specs/components before pulling the trigger.