I wonder what this will mean for the various forms of on-call. I've seen several...

I wonder what this will mean for the various forms of on-call. I've seen several policies, I'm sure there are more:

- "Ad-hoc" on-call with no process and you just get a phone call after hours from the boss

- "Voluntary" on-call with a stipend, rotation based among a particular team

- "Mandated" on-call with full over-time pay / penalty rates

Are all of these now up for review? Presumably anything written in a contract takes precedence I suppose.