CO. The itinerary is actually EZE-IAD-LAX-TUS (B Class), all UA metal, ticketed by CO (TUS-IAH-GIG outbound, B Class). I'm trying to max EQMs.

Should I contact CO? If so, should I do it now or wait until the last minute (March itinerary, hoping Y is full). I'm switching from DL to UA and have no status on UA/CO.