DAVx5 tries to sync via mobile internet even when "sync only over wlan" is active

[GunterKramp]

Probably since the last update (now V 4.4.8-ose) DAVx5 tries to sync via mobile internet as well as via WLAN.
Before it synced only via WLAN as is configured in the settings with "sync only over wlan".
The sync efforts via mobile internet cause error notifications to pop up as the server FQDN of our Synology DSM is only resolved correctly on the local network. The Server is not supposed to be reached via WAN for security reasons.
Sync works as intended via the WLAN even though the errors keep popping up on every sync.
My phone is android 10.
I use netguard firewall that simulates a VPN to enable a firewall without root. Switching this of does not change anything.
Setting "VPN needs Internet connection" is activated
Can anyone help to resolve this ?

[sunkup]

I don't see how this could have been introduced by the last update, but if you send us your DAVx5 logs, we will be able to take a look and assist you further. You can see how to securely share the logs with us here: https://www.davx5.com/support#c335