Reddit Sync will have a full page sign up for his new app, Lemmy Sync, when you open the app on June 30th (also kbin support coming!)

Source:

https://www.reddit.com/r/redditsync/comments/14hb7h3/comment/jpcby48/

Correction: the pop up for Lemmy should start to appear sometime this weekend

https://www.reddit.com/r/SyncforLemmy/comments/14fhi9u/using_sync_for_reddit_as_a_marketing_tool_come/jp2bts8/

Also apparently confirmed in discord that kbin support will be coming:

https://www.reddit.com/r/SyncforLemmy/comments/14g8eix/q_will_sync_for_lemmy_be_able_to_handle/jp4uvh5/