i’v read your post between 2 meeting, so might be completly off topic.
i’ve seen this in the doc
AccuracySec=
Specify the accuracy the timer shall elapse with. Defaults to 1min. The timer is scheduled to elapse within a time window starting with the time specified in OnCalendar= , OnActiveSec= , OnBootSec= , OnStartupSec= , OnUnitActiveSec= or OnUnitInactiveSec= and ending the time configured with AccuracySec= later. Within this time window, the expiry time will be placed at a host-specific, randomized, but stable position that is synchronized between all local timer units. This is done in order to optimize power consumption to suppress unnecessary CPU wake-ups. To get best accuracy, set this option to 1us. Note that the timer is still subject to the timer slack configured via systemd-system.conf(5)'s TimerSlackNSec= setting. See prctl(2) for details. To optimize power consumption, make sure to set this value as high as possible and as low as necessary.
Note that this setting is primarily a power saving option that allows coalescing CPU wake-ups. It should not be confused with RandomizedDelaySec= (see below) which adds a random value to the time the timer shall elapse next and whose purpose is the opposite: to stretch elapsing of timer events over a longer period to reduce workload spikes. For further details and explanations and how both settings play together, see below.