The "Airbus A32S" technically stands as "A320 Series" which is a generic term normally to describe the A319-100, A320-100, A320-200 and A321-100 models that Airbus Industrie makes.

With United's new low-cost unit Ted's arrival, The Airbus A32S designator is used to differentiate Ted aircraft from mainline A320-200 aircraft. Ted aircraft, however, are also A320-200s but are configured with all-economy (Economy Plus + Economy) cabins whereas the mainline A320-200s have 12 First Class seats + Economy Plus and Economy.

Therefore, to answer your last question, there is no upgrade option on Ted Operated by United flights because there is only coach seating available.

Hope that helps!

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