I just have a question that's been nagging me.

1. If I book an economy fare, and then select an E+ seat for an additional fee, does this fee get accounted for in the upsell offer I receive for First or Business?

2. If I book Economy Plus by selecting it in the booking screen, it still gets booked as an economy fare + a seat assignment charge (unlike Premium Plus, which is a separate cabin), so does this affect the amount of the upsell offer I receive for First or Business?

3. If the answer to #1 or #2 is no (as in, I get the same upsell offer as other economy passengers), if I take the upsell offer, do I get refunded the Economy Plus fee?

The answer is much more straightforward for Delta, since Delta codes Comfort Plus as a separate cabin, but I cannot for the life of me find the answer for United...