I actually did this trek as a homestay trek going from Sabu to Digar in one day but I don't recommend it. I started at dawn and reached Digar just as night was falling its better to cross the pass in two days. This is a nice way to enter the Nubra Valley and Digar is a beautiful unspoiled village. The trek itself is nice but the whole way up the Digar La it is essentially the same view of the Stok range that you get from Leh. The other side of the pass down to Digar is the best part of this trek. The trail descends through a series of beautiful meadows open at one end to the distant white peaks of the Karakorum. From Digar it is about two hours down a new road (not marked on most maps). It is best to hitch from there although there is not a lot of traffic so you may have to walk a ways, but the walk along the road is hot, there is not much water at all, and the view doesn't change much because the valley is so wide, so getting a ride is definitely the preferred way to exit.
Do It Yourself Information
I got fooled where there is a meadow the maybe 45 minutes past the rock shelter, the trail goes off the valley to the right and then climbs the wall of rock to the north side of the valley which is the Digar La. If you start scrambling over big boulders and haven't seen a trail in a while you are going the wrong way.