Hopefully less than 5 years. Most movie rights last for a year so if we don’t hear anything in a year, then we can assume it won’t happen- at least not with the same company. Sarah would get the rights back and be able to sell to someone else if they don’t do anything with it. It has already happened when Acotar was supposed to be a movie series.
There was going to be a TV series, you can read the available information here: Queen of Shadows (television series), however, it seems the project didn't work out in the end, and they are focusing on ACOTAR now.