Check when and if Initial sync ran sucessfully

Hi,

I am finding it hard to understand where does sync service reports that an Initial sync was initiated.

I have scanned through event viewer with events 904 and all event points to a delta sync.

Is there an event thats generated when you start an initial sync?

Is there any other way to indentify when in past somoeone initiated an initial sync?

Sync service version : 1.1.343.0