This will probably cause another parallel market, a black market in unlicensed exchange houses. It’s a dumb way to do it. They’ll run out quickly as the people who sell $ at 2000 stop selling. 
This could work (for a while) only if the official exchange rate is changed to match the 2000, meaning that the central bank would have to supply banks with enough $ to allow them to change for their customers with no restrictions. This would deplete a chunk of reserves.
Therefore, either this is a totally idiotic decision ... or a prelude for a new peg at 2000.
