Why did our cloudflarestream subdomain change?

We’ve been using Cloudflare stream successfully for the last several weeks for product videos on our consumer facing website.

We essentially embed an iframe with /video-id/iframe?autoplay=true.

On 30th August everything broke

Upon investigation our subdomain changed before it was customer-m033xxxxxx and now it’s customer-409kxxxxxxxx

What happened? Why did this happen? I’d like to believe we are responsible but I can’t see a way that it could be regenerated, if CF is responsible then this is deeply disappointing.

Either way would be good to get some insight