Kefir-Leban is a soft kefir curd cheese that has not been mold developed. It is essentially pressed kefir curd. Kefir cheese at THIS stage should be definetely probiotic. However, as the whey has been removed, its only half as probiotic as homeade kefir from real kefir grains. (I do suggest real kefir over the cheese.)
However, the next step is usually then to innoculate it with a cheese making culture and either wrap/pack or oil dip it.
It really depends on what the actual product is that you have. I would suggest checking out the yahoo group Real_Kefir_Making and seeing if they can identify just what "Lebni" is for you.