backup of deleted user, sync issue

[AlexL]

Had something unexpected happen yesterday while investigating an issue with backup object count for a customer.
Veeam was apparently doing a backup of a deleted user mailbox/onedrive etc, backup job configured as entire organization.
Both logs in ProgramData, the html reports and Get-VBOEntityData show a recent backup (of today), but account is NOT existing nor visible in MS365/EntraID Admin Centers.
Customer says this user was deleted a month ago!

So I did some further digging and looked at the synchronization, then things became very odd:

(Get-VBOOrganizationUser -Organization (Get-VBOOrganization) -DataSource PreferLocal).count
5417

(Get-VBOOrganizationUser -Organization (Get-VBOOrganization) -DataSource Production).count
5107

rather large difference, Get-VBOOrganizationSynchronizationState shows succesful incremental sync in the last 24 hours
but ok, sure, could be

(Get-VBOOrganizationUser -Organization (Get-VBOOrganization) -DataSource PreferLocalResynced).count
5417

this is weird, after resync same number?!?

(Get-VBOOrganizationUser -Organization (Get-VBOOrganization) -DataSource PreferLocal).count
5417

also, unchanged

Start-VBOOrganizationSynchronization -Organization (Get-VBOOrganization) -Full

(Get-VBOOrganizationUser -Organization (Get-VBOOrganization) -DataSource PreferLocal).count
5107

ok, after a FULL manual resync suddenly local = production, and after another backup the logs do NOT show this user being in the backup.

How can this possibly be explained? Is this expected behaviour? Is this a bug perhaps?
Would it be better to schedule a daily full sync before a backup job?
Since the numbers changed by almost 300, this also means that up to 300 licenses to many were used.
Get-VBOLicensedUser also shows a recent backup (yesterday) for this "deleted" user.

[pybfr]

Hello,
Support will be much better positioned to go to the bottom of this.

[Polina]

Hi Alex,

When you use the 'PreferLocal' parameter, VB365 uses cached data. If there were any issues with updating the cache, the information might not be up-to-date. Try using the '-DataSource Production' parameter.

And, indeed, it's worth involving support to at least investigate why the cache is not up-to-date.

Thanks!