@edwardian-dreams wrote:

I think they’re working their way through and adding the exempt categories 


It's just typical of ebay to make things more complicated than necessary with all the resulting confusion, bugs and weird edge cases. They should just open up the various weights of 2nd class Large Letter where the seller feels it's suitable when creating the listing maybe with an advisory that the cover is limited to £20.

 

There is no need to police postage options by category they are just making things hard for everyone.