[bug ?] Calendar update not instant

Hello,
This week I modified one of my heating calendars: in short, I deleted all the events.
The sync in Gladys didn’t happen, no change.
I forced the sync but still no change.
I left it running but nothing more.
And this morning I removed the sharing of this calendar (just in case), I resaved the configuration and restarted a sync and the events disappeared.

Could there be an issue with recurring events or an automatic sync that isn’t working anymore?

I have my availability logs for analysis if needed.