Page Delivery Configuration Anomaly

Hello community!

I wanted to get everyone's thoughts on page delivery rules.

Today I had an experience where an XT activity pointing to a lower environment was exposed to our production environment. This was totally unexpected because the delivery rules explicitly set the domain to something like foostg.com, for example. However, the experience was exposed to foo.com (again an example for added context).

After identifying the issue I ended up having to add a Domain does not contain template rule for foo.com.

The thing that scares me is this could happen with any activity in development, inadvertently exposing it to a live audience.

I experienced this once before years ago, where a manager asked why an A/B test that was in development, was visible in production? I disputed the claim but could never figure out how this was possible. Now I think I know how. But why would an activity be delivered to two different domains when only one was specified?

Given the above explanation, is this behavior expected? I can't imagine the answer being yes, but curious what others have experienced. I wanted to get some insight before opening a customer service ticket to see if there's a bigger issue going on here.

Thanks,

Brion

Cc: @amelia_waliany