2 new "dead" gateways after upgrading to 2.3

[ChristianHaag]

We have 2 gateways named WAN1GW and WAN2GW. Their IP addresses are 80.147.X.X and 87.128.X.X

After the upgrade to 2.3 two new gateways were appearing. They are named WAN1_PPPOE and WAN2_PPPOE. The IP addresses of the new gateways are 217.5.X.X

Both new gateways have the status "Offline" in the dashboard.

I cannot delete them in System > Routing > Gateways. There is no delete icon.

Status > System Logs > System > Gateways show errors like:

dpinger / send_interval 500ms loss_interval 2000ms time_period 60000ms report_interval 0ms data_len 0 alert_interval 1000ms latency_alarm 500ms loss_alarm 20% dest_addr 217.5.X.X bind_addr 80.147.X.X identifier "WAN2_PPPOE "

dpinger / WAN1_PPPOE 217.5.X.X: Alarm latency 0us stddev 0us loss 100%

The two new gateways are part of our gateway group under System > Routing > Gateway Groups. Their tier is set to "Never".

I know this somehow looks similar to https://forum.pfsense.org/index.php?topic=109706.0 However, I thought opening a new thread might be better.

pfSense is working nicely, our two WAN gateways are up.

Any ideas?