I have seen a lot of people write this but I don't understand how. Shouldn't there be a black market rate in that case? Is there one? Some quick Googling gave no articles.
Also, if you are an oligarch who plans to load your private plane with suitcases of dollars and fly to the Cayman islands, you are probably sanctioned, so that is out of question too.
There are two things holding the ruble high: 1. All exporters have to sell 80% of their FX income in 3 days 2. The import has shrunk dramatically and it's hard for people to travel to other countries (so individuals and businesses don't need that much cash to begin with)
It would be interesting to know the "real" rate to get the scope of the currency control.