Where I work people just call if you show as available. Imo this should warrant extra hazard pay.

I have to manage my team for a few hours every night in-between supervisors duty cycles, we were getting slammed with issues one night and one junior coworker messaged me about something serious.

Without thinking I called her on teams without asking first, when she answered I heard a baby crying, once I found out it was my call that woke him up since he would only sleep in her lap I felt like crap. I ended up taking over the issue from her out of guilt and have never called anyone without asking again.

There's one guy at work who refuses to warn people. Like hell, no. You can wait while I try to find my headset.