Zero Hour
A countdown to one moment for everyone. Give it a date, a time and a time zone, and 17:00 in London is the same instant in Tokyo and New York, with each visitor told what that is on their own clock. It repeats daily or weekly for cut-offs, and a screen reader hears one sentence instead of every second.
Every Friday at 17:00 London time. Read from Tokyo or New York it shows the same time left, plus the moment on the visitor’s own clock, and at zero it rolls on to the next Friday, so it never runs out.
The same component, plain and centred, with days off and separators on: a daily 15:00 New York cut-off that rolls over to tomorrow’s at zero.