Getting dragged to a wedding do on Saturday evening in Abergavenny, travelling over this afternoon so will have tomorrow morning to potentially fit in a ride if I stick the bike in the back of the car.
Where's good in the local area?
Depends what you want to do. If trail centres then Cwmcarn is reasonably close but not local, and a little further away you have Forest of Dean. If natural trails then plenty of local stuff around, just need an OS map. I can forward gpx routes of some of the recommended routes in 'Wales mountain biking book' for natural trails in that area if you forward your email address. I haven't done all of them though so couldn't comment what their like.
The blorenge is good and right next to Abergavenney for a short ride. Bits of it might be muddy though.
loop up through Mynydd Du Forest maybe or howabout
climb up from grwyne-fawr-reservoir side head over to Y Das and then return back down past the resi if the weathers good you'll get cracking views from Y Das and back down past the resi
http://www.mtbbreconbeacons.co.uk/hubs/talgarth/grwyne-fawr-reservoir