What is the earliest notification for when a new coin appears on Binance?

I am curious.
Suppose FOO coin gets launched on Binance.
I know it’s possible to view trades realtime with WebSocket API, and detect the first FOOBTC trade.
But someone must have made that first trade, right?
So how did they do it?
Is there any prior “FOO coin is now available for trading” announcement through WebSocketAPI or API, or is someone just spamming Binance with trades until one goes through?

You can check Binance Announcement page (example) to know in advance the new trading pairs. Additionaly, you can use https://t.me/binance_announcements (for example) to receive alerts automatically.

When the pre defined open time is reached, users can start posting orders.