Alerting across multiple sites with different business hours

Thank Stuart,

I like the dynamic group idea and rules for each.
I might play around with that idea a bit more.

I was hoping to not have to do a heap of rules and escalation chains.

The main issue is managing the rules and escalation chains.

I've created a matrix and gone through every days opening hours for every site.
I've done this across every time zone.
Then I've looked for any marked any duplicate open periods. This lets me consolidate some sites to a single rule / chain.

But, I'm still left with 151 unique opening hours across those sites that we need rules for and chains based on the time zones they're in.
And then we hit a problem should the opening hours get changed to fall outside of what we've created dynamic groups for.  This is a likely possibility as the customer is a large retail brand across multiple countries.

Tbh, I'm not liking my chances of simplifying the rules & chains....and am probably just putting off the inevitable.

Keen to hear any other ideas about this.

Cheers,