Earlier quoted context omitted.
You still have to ask for times they are available. That never changes. With UTC as the global time standard, you don't have to try to figure out time offsets. You just say "I'm available from 8 to 12" and they say "I'm available 5 to 9" and you make the call at 8. The alternative is "I'm available 3 - 7 London time", the other guy is available 12 - 4 Pacific Time, and you have to get out a calculator to figure out w…
Most of us who have to deal in multiple time zones have a Web Page/Dashboard/App of clocks with all the time zones that we deal with. 45' away from me I actually have a physical wall of clocks with cities noted above them. I know that my partners/customers/colleagues in all countries are available for calls from roughly 9:00 AM to 5:00 PM without ever having to ask them. That's basically what TimeZones do for you - t…
... which you could dispense with if everyone went on the same time base.