Timers and Timelines are evaluated once per frame. They deduct tick delta seconds then check if they have finished.
Considering the following test actor.
Frame Times
60 FPS (16.667ms)
80 FPS (12.5ms)
100 FPS (10ms)
120 FPS (8.333ms)
The above test speed is 86ms (0.086).
60 FPS
5 * 16.6667 = 83.3335ms
6 * 16.6667 = 100.0002 (0.1) interval in the log results
80 FPS :: 7 * 12.5 = 87.5 (0.088)
100 FPS :: obvious 0.09
120 FPS :: 11 * 8.333 → 91.663 (0.092)