Timed schedules are delayed

I have ~50 periodic scheduled events (every 30 min). The problem is that when I schedule another task to be done at a specific time (e.g., every Wednesday at 1:00), the timed scheduled task starts with ~7 min delay (starts at 1:07 instead of 1:00).

My guess is that this is happening because several other tasks are queued ahead of the last scheduled task. Is there a way to get the timed task "ahead of the queue" so that it actually runs at the scheduled time?

Start by reproducing the delay with several periodic jobs and one Wednesday-at-1:00 job. Read the scheduler's job selection and execution flow, then determine how queued work affects scheduled timing. Done means the reported timing behavior is understood and the selected fix is verified with a reproducible test; no source files or tests are named in the issue.

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