File server backup enabled VSS - daily job is making full backup

Hi,

Our Windows file server backup is taking extremely long so I'm trying several settings to see if it helps performance.

Full backup job ran last weekend.

Monday I enabled multistream in the plugin options (started with 2 streams).

Tuesday I increased to 4 streams but also enabled VSS (all jobs before did not had VSS enabled).

This morning I noticed that the daily incremental job was still running.

When looking at the resource monitor on the file server, I see files being touched by the backup that have not changed in a day and should not be part on the incremental daily job.

So it looks like it's doing a full backup once VSS was enabled even though the plugin option is set to incremental.

Is this normal behaviour that after selecting VSS, at least the first incremental is actually a full backup?

NV 11.4

Thanks,

Richard