I noticed that the trigger is a new contact establishment or openVPN is stopped.
MorningReconnect here:
Oct 21 01:10:00 famschamrouter ipfire: ConnSched disconnect
Oct 21 01:10:00 famschamrouter pppd[4532]: Terminating on signal 15
Oct 21 01:10:00 famschamrouter pppd[4532]: Connect time 437.5 minutes.
Oct 21 01:10:00 famschamrouter pppd[4532]: Sent 392473603 bytes, received 15497873 bytes.
Oct 21 01:10:00 famschamrouter pppd[4532]: Connection terminated.
Oct 21 01:10:00 famschamrouter openvpnserver[7877]: event_wait : Interrupted system call (code=4)
Oct 21 01:10:00 famschamrouter openvpnserver[7877]: /sbin/ip route del 10.80.147.0/24
Oct 21 01:10:00 famschamrouter openvpnserver[7877]: ERROR: Linux route delete command failed: external program exited with error status: 2
Oct 21 01:10:00 famschamrouter openvpnserver[7877]: /sbin/ip route del 10.90.147.0/24
Oct 21 01:10:00 famschamrouter openvpnserver[7877]: ERROR: Linux route delete command failed: external program exited with error status: 2
Oct 21 01:10:00 famschamrouter openvpnserver[7877]: Closing TUN/TAP interface
Oct 21 01:10:00 famschamrouter openvpnserver[7877]: /sbin/ip addr del dev tun0 local 10.90.147.1 peer 10.90.147.2
Oct 21 01:10:00 famschamrouter openvpnserver[7877]: Linux ip addr del failed: external program exited with error status: 2
and here I stopped openVPN manually
Oct 21 02:35:49 famschamrouter openvpnserver[13717]: event_wait : Interrupted system call (code=4)
Oct 21 02:35:49 famschamrouter openvpnserver[13717]: /sbin/ip route del 10.80.147.0/24
Oct 21 02:35:49 famschamrouter openvpnserver[13717]: ERROR: Linux route delete command failed: external program exited with error status: 2
Oct 21 02:35:49 famschamrouter openvpnserver[13717]: /sbin/ip route del 10.90.147.0/24
Oct 21 02:35:49 famschamrouter openvpnserver[13717]: ERROR: Linux route delete command failed: external program exited with error status: 2
Oct 21 02:35:49 famschamrouter openvpnserver[13717]: Closing TUN/TAP interface
Oct 21 02:35:49 famschamrouter openvpnserver[13717]: /sbin/ip addr del dev tun0 local 10.90.147.1 peer 10.90.147.2
Oct 21 02:35:49 famschamrouter openvpnserver[13717]: Linux ip addr del failed: external program exited with error status: 2
Oct 21 02:35:49 famschamrouter openvpnserver[13717]: SIGTERM[hard,] received, process exiting
Oct 21 02:35:50 famschamrouter vnstatd[9357]: Interface "tun0" disabled.
