CW Season Finale Dates

The CW has announced their spring finale dates. Extrapolating backward, there are no gaps between the finales and the next episodes. Supernatural and Arrow will run every week from March 29 to May 17, Flash from April 10 to May 22, Legends of Tomorrow and Black Lightning from now until April 9 & 17 (respectively), and Supergirl from April 16 to June 18. The last three were already known, I'm just mentioning them again for completeness.