Russian speaking means Russia, Belarus, Ukraine and some other countries of the former USSR. Have heard that if you are not a NCO (sous-off' ) or a valuable specialist of some kind (radio op, mechanics, etc.) you will probably not be re enlisted after 8 years. This is how it always worked in the ‘regular’. We have ex French paras, or Marine Infantry types, who join the Legion after they have done a 8 year service.
Heard also, French count for only 7% of the Legion intake today. The Army just does not attract: shit pay, shit food, shit job and now 17 ½ yrs for a small pension. Any wannabe who speaks some French has a bit more chance in joining, imo.
It will help too for promotion and courses and reenlistment.