Yet another epic day starting from Lastra (this time with light winds and an easy climb out). Some struggling over the back on the ridges N of the road, then a big climb to around 3500m where the wind was SE. The convergence line swept to the NE, but determined to reach Salamanca we (Mike and I on the tandem and Eldad, Anton on there solos) ended up low and then down to the N of the convergence into a headwind. Chino turned back to the convergence then flew an out and return back to Piedrahita getting to near 4000m. Usi, whose radio went down carried on along the convergence line to near 100km on his Epsilon.