This situation isn't too similar to the Manchester Fiasco - All they put up the first day was seating. So a large number of us bought these, believing the venue to be all-seating (we clicked on the 'best available' option. The only way to solve this (I.e. get Gold Standing instead of Seating was to phone up & kick up a fuss). Yvonne got lucky - she had hers transferred. I wasn't quite so lucky - after 3 phone calls (& I was quite persistent the last time) I got them to cancel them (for a price), so I could rebook.
Hence the only advice I can give is what Yvonne told me - phone up & get to speak to the highest person available (don't be fobbed off by an operator). Just be really persistent & hope they change them. In the UK alot of it depended on which operator u got through to. One would say'your phoning up to swap BJ tickets right? Another would say, sorry we only sell standing tickets.
Thats all the advice I can give, although I'm sure many of u have tried this already
Good luck anyway.
Mike