In reply to goatee:
Ahh. I remember discussing snow conditions and the vultures you saw after one of your previous tips here.
Have a good trip and I hope the bus works out for you.
If not, the Massat (Arac) valley / Seix (Salat) valley are not too bad for thumbing a lift - Lots of locals do this, especially on market days.
Probably a little more difficult, though not impossible, to cadge a lift up the Garbet valley for the final stretch to Aulus.