Well, Lathander was one of the three deities available to the cleric in the original series. And he also returned after the fourth edition retcons. If Larian had not included him in the list of deities, I would have been surprised.
Lathander is alrdy added
Yes, I know.
My understanding until now was that Lathander was not included, as reported by others in this forum in the past. I am not one of those playing the EA game so I don't know these things first-hand. So if Lathander truly is available as a player-choosable deity, then I'm good. But I still stand with wanting to see all the major deities in the game. What those might be I don't know, as I'm not up to speed on which deities retain major deity status in 5e.