Azure Durable Functions, Python: singleton non-overlapping cron

Question

I want to run a cleanup function as part of my bigger Azure Function in Python. Similar to cron, but needs to be:

• non-overlapping/singleton, can't have two cleanups running at the same time,
• long running but short cadence, e.g. it runs for ~5-20 minutes, but I want the next one to start soon, e.g. 1 minute after the previous finished,
• automatically run, no HTTP calls or other triggers needed.

Right now I have this, but not sure if it's the right approach, feels like a hack.

What do you think?

Docs that have helped me get here: timers in durable functions, eternal orchestration, timer triggers and singleton orchestrators.