Do you mean the Brevet 25,000?
If so, then AIUI it could count as the 1300, 1000 part of one of the SRs, or the other points towards the 250 total. In other words, it isn't PBP, LEL or an Arrow! (As it's an AUK award, longer rides than the nominated distances can be used)
[Edit: originally typed 1200 instead of 1300]