I live opposite the 2 main flying sites and it looks as if you can stay up as long as you like!
The photograph shows 12 paragliders and 2 hang-gliders up at the same time... this is very rare! Must have been a good day! Sometimes busy at weekends but during the week.... sky's the limit!
Access
Drive south (1.5 days from Home Counties) or fly to either Toulouse or Rodez. (Rodez is Ryanair from London Stanstead and Toulouse is Easyjet, BA etc from London Gatwick.Low cost carriers also fly from Bristol and Southampton. There are flights from other airports further north but seem to be seasonal.)
St Antonin is 1hr 15min drive from Toulouse and Rodez.
Rules
Not sure. Occasional jet fighters flying low through valley but not sure if there are any regulations relating to this. Will try to get confirmation!
WEATHER
Non that I can see but I'm no expert. It seems to suit beginners and experts alike.
Check the website..For Hang Gliding and in French but looks like good info regarding takeoff and windsock location etc.