LACP 802.3ad has two settings for periodic transmissions / LACPDU, fast and slow.

Currently, the LACP pairing between Metal instance LACP and it's attached network (ToR) only allow for LACP slow.

For certain use cases, LACP fast can enable more elegant / responsive failure behaviors for systems deployed above Metal instances.

Being able to specify that an instance's LACP configuration from the switch side be "fast" would enable this functionality.