@dyamamoto I imagine your problem is more pronounced now because COVID-19 triggered a lot more Work From Home users who must connect over VPN.
Often it is a reboot from some patch installation that causes clients to loose their cache and suddenly not be relevant for content. I would like to see the AD Cache persist across reboots instead of be cleared out like it currently is. Wouldn’t be the first time someone asked for the AD cache to be preserved: Cached AD Information gets overwritten by AD Connection Error
Unfortunately, I don’t have much experience with Azure AD so am not so familiar with the issue described by @Discoboy. I’m surprised that Azure AD and on-prem AD would not be the same in this case. Where would one start to learn how these differ?