Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.
The since() method of Temporal.PlainTime instances returns a new Temporal.Duration object representing the duration from another time (in a form convertible by Temporal.PlainTime.from()) to this time. The duration is positive if the other time is before this time, and negative if after.
This method does this - other. To do other - this, use the until() method.