You can get a “new or returning subscriber” in real time via
- chat (USERNOTICE) - https://dev.twitch.tv/docs/irc/tags#usernotice-twitch-tags
- pubsub - https://dev.twitch.tv/docs/pubsub
- webhooks - https://dev.twitch.tv/docs/api/webhooks-guide
You can get a “new or returning subscriber” in real time via