I saw people sledging at 10pm, there is enough light but you have to be careful, especially if conditions are the same as last week, as rocks were starting to show through. lifts stop around 4-4:30pm depending on how far up the mountain you are. Furtherest away closes earliest. I recommend the further slope from the Rila to the right as you stand looking out of the Rila, as this has the most artificial light from shops and houses...
Robo, have searched for a lot of minutes about this post coming from Hristo:
I am from Sofia, Bulgaria.
There is no night skiing in Borovec for now and it is not sure whether there will be this season.
On the other hand there is night skiing every evening on Vitosha, which is a mounthain next to the capital Sofia