Okay so finally remembered that I noticed this ages ago but didn't do the research at the time.  We have a case of the old "Glasgow Cathouse 94" again, not sure why Oasis can't label stuff right but there you go.
Have compared Some Might Say from the re-master to Some Might Say from the following:

Slane Castle 22/07
Zeebruggers 21/07
Duren 09/07
Eurokennes Festival 08/07

Rosklide 30/06

Further analysis of other tracks and the chatter between also rules them all out.
We know it isn't glastonbury.  He says "Better than Glastonbury this" after Hello which could either strongly hint that Glastonbury is the following night, or that they recently played it. 

So that leaves us with the following:

Madrid 18/07
Beach Park; Irvine 15/07
Beach Park; Irvine 14/07
Out In The Green Festival 07/07
Fauvier Fesitval 05/07
Palalido 03/07

Now we know, thanks to youtube search "Oasis live @ Irvine Beach" and finding "Rock n Roll star audio" we thus know that the first night of Irvine Beach was recorded at the Sounddesk.

So is it Irvine Beach or Bath Pavilion?  Well,  I'm going to suggest the former due to all the delay on the vocals - It sounds almost exactly the same as eurockene but is just a touch difference.  Glastonbury was a very nasal gig for Liam and I think we would hear it on this recording if it was Bath.  I mean it could be any of them but can probably assume it's an English audience with the Glasto reference and the added bonus of knowing it was recorded.  I think Irvine Beach was a festival anyway?

Any thoughts?