I coincidentally just got this information from a support engineer during a support case with a different subject:
During my research I have found another bug that may affect you:
596104 - VCMP guest fails to load config with HA trunk configured
_Symptoms:_
If a VCMP guest is configured with an HA trunk (such as, when loading such a configuration created with an earlier version of BIG-IP), the configuration load will fail with a message similar to the following:
err mcpd[5926]: 01071569:3: Ha group ha_group threshold for trunk your_trunk_name_here 1 is greater than the maximum number of members 0.
_Conditions:_
This occurs when loading a configuration from a VCMP guest created in a previous version that had an HA trunk configured.
_Impact:_
Unable to load config with HA trunk on VCMP guest.
_Workaround:_
Manually setting the HA trunk threshold to 0 will allow the configuration to load; however, this disables the HA trunk feature.
There is no HF or EngHF I am aware of for the moment.
This is obviously the bug you are hitting, too.