Actually, it's not suspicious, it's pretty cut and dried - this is a classic example of a hijacked account. A pity, I'd love to have that bike.
Note the 'don't use ebay ask seller' comment. This is a sure sign of a hijacked account. Also check the seller's feedback - no history of cycling sales or purchases.
Had a similar experience, when the price seems to good to be true it probably is. Item location was London so asked him if I could pick it up. He said yes, as long as I paid on the day. asked him for a number since it sounded dodgy. And yes it was he responded that he does not use the phone!!!!! Ebay have since removed his add. No money lost!!!!🙂