4:20 Flashback: Who’s birthday is it anyway?

420 Flashback 6-3-19
This would have been the birthday of longtime keyboardist for one of my favorite bands. Heart attack got him in 2009.
Answer: Billy Powell of Lynyrd Skynyrd from 1972 until his death in 2009. Powell called police saying he was having trouble breathing and emergency services tried to resuscitate the musician but he was pronounced dead an hour later.