There's been multiple waves to Lemmy.

• Early 2020: Lemmy's creators make a post on /r/communism, announcing Lemmy and offering to set up an instance for the subreddit to migrate onto. This instance becomes Lemmygrad (which is still run by Lemmy's founders/the people who also run Lemmy.ml).

• Mid 2020: Federation comes online for Lemmy. Lemmy's founders make a post to /r/Linux, advertising Lemmy and getting people to join. This is the wave I was in, originally, but the folks from wave 1 scared me off.

• Then there were a few other waves. I wasn't around for any of them, but I know in late 2021/early 2022 Beehaw was created. I believe Beehaw split off from Tildes, which is another Reddit clone run by a former Reddit admin (who also made AutoModerator).

• Then, in May 2023, we saw the first wave of people coming over from Reddit. As the other person mentioned, there were really multiple smaller waves... usually corresponding with an announcement the Reddit admins made. The blackout gave the biggest wave.

Since the start of July, it's largely petered back. A lot of the folks who are diehard anti-Reddit are here, but until Reddit fucks up again it'll probably quiet down.

Reddit will fuck up again, mind. Digg didn't die instantly, either - it was a slow, drawn-out death.