I had a problem yesterday. I scheduled a live event but didn't specify ingestion settings in advance as I wasn't sure how much of a pipe there'd be.
Then when I went to connect at the event (livestream studio) I got the error 'please set bitrate in ingestion'. So I went and did that. But the error kept coming. I changed it, resaved, error. Over and over.
Eventually I had to set up a new event. Worked fine.
But the original url had been widely promoted, so it was a mess.
Anyway I learnt my lesson. Set that ingestion well ahead of time and test it.