On Continetal Micronesia, the premium cabin is marketed as "business class" on the narrowbody aircraft. On DC-10 aircraft, the premium cabin is "BusinessFirst." "Business class" is comparable to domestic first class, however in my limited experience (two flights in CS premium) the service is better and features sparkling wine. Their "BusinessFirst" is presumably the same as Continental's, however I have not flown BusinessFirst on a Continental Micronesia flight.

Business class seats are available for complimentary Elite upgrades. BusinessFirst seats are not available for complimentary upgrades. Business class inventory is in C/D/Z, with upgrades coming out of the Z bucket. On both of my flights, mechanics occupied the two business class seats in row one. BusinessFirst inventory is in J/D/Z, with upgrades coming out of the Z bucket.

In short, flights with J will not be eligible for elite upgrades. Flights with C inventory are eligible for elite upgrades. As for EUA, I don't know the answer and I don't think Continental's reservation sales agents' have any knowledge of the subject.

Another issue to note is that a very limited number of CS flights from GUM to Asia are on DC-10 aircraft with J inventory, such as flights to Tokyo (NRT).

Finally, make sure you carry the printed Elite guide (I did on this trip). All staffing at TPE is performed by Thai Airways International (TG). The ticket agent refused to upgrade me upon check-in. At the gate, I asked for the upgrade and presented the book, in addition to my card, and was upgraded after the gate agent telephoned a "supervisor." I assume that due to CS's limited flight schedule, travellers will be likely to encounter similar situations at many other stations. Be prepared.