Hi,
I'm looking at doing a miles + copay upgrade on UA950 LAX - IAD - BRU on 5/24.

Here's a couple of questions I have :
1) on mobile.united it shows for the LAX-IAD leg 38 booked out of 49 possible for C class. For the leg IAD - BRU, it shows 29 out of 40 possible for C class.
On UA website however , it shows
Available Cabins: F2 FN2 A2 ON0 O0 J2 JN2 C2 D2 Z0 ZN0 P0 PN0 R0 RN0 IN0 I0 Y9 YN9 B9 M9 E9 U9 H9 HN9 Q8 V8 W7 S6 T2 L2 K2 G0 N0 XN0 X0
According to mobile, there are 11 seats available on both legs, but to UA; only 2 are available.
Which one is correct here ?

2) Assuming that 11 available seats is correct, I should have a good chance of clearing the miles + copay , but probably only at the gate ? (my orginal booking class is T)

3) If only the LAX - IAD segment clears, and not the IAD-BRU segment, should I get the $550 copay automatically back , or would I need to request that back ? The miles part (20000) is the same for LAX - BRU and LAX - IAD and the $75 is waived since I'm a 1K ?

Thx,
Erwin