FYI, I'm not sure if this has anything to do with your COC talk, but thought I'd pass it to you. Most ramp functions at line stations fall under the PCE agreement (LAS, PHX) The following are classified ramp stations for UA. I think the ramp contract calls for mandatory ramp to work the ramp with a set number of departures. You'd have to check with a ramp person. But currently these are the classified UA ramp cities. Hope this helps and doesn't confuse.
Baltimore, Washington, D.C., Detroit, Milwaukee,
Boston, Newark, Philadelphia, Buffalo, John F. Kennedy International Airport,
LaGuardia, Pittsburgh, Cleveland, Dulles, Chicago, Omaha, Denver, Los Angeles,
Honolulu, Atlanta, Salt Lake City, Minneapolis, San Diego, Sacramento, San
Francisco, Portland, Seattle, Tampa, Fort Lauderdale and Orlando.
Baltimore, Washington, D.C., Detroit, Milwaukee,
Boston, Newark, Philadelphia, Buffalo, John F. Kennedy International Airport,
LaGuardia, Pittsburgh, Cleveland, Dulles, Chicago, Omaha, Denver, Los Angeles,
Honolulu, Atlanta, Salt Lake City, Minneapolis, San Diego, Sacramento, San
Francisco, Portland, Seattle, Tampa, Fort Lauderdale and Orlando.