When using Honeycomb to set VPP interface ethernet configuration:

PUT /restconf/config/ietf-interfaces:interfaces
{
"name": "GigabitEthernet0/8/0",
"v3po:ethernet":

,
...
}

then settings are accepted and moved into configuration data, but no changes are made to VPP and the following warning is logged:

WARN | qtp222012497-278 | EthernetCustomizer | 257 - io.fd.honeycomb.v3po.2vpp - 1.0.0.SNAPSHOT | Unsupported, ignoring configuration Ethernet{getMtu=1500, augmentations={}}