You apparently aren't very familar with atomic clocks.
Accuracy is not a problem.
There are measurable effects to time due to acceleration.
>>There are measurable effects to time due to acceleration.
“To time”.
Presumes time exists as an entity that is separate from the system that is being observed.
Certainly we can see changes in observable phenomena within a system; changes that are relative to the velocity of that system.
The concept of time is a human construct that is derived from observing these state changes within the system.
If the system no longer changes state, what happens to time?