Ideally, it should have a temporary convoy, like a replace window, and the player can complete it at any time by pressing the Done button. Players can start over until he press the Done button.
Typically, such upgrade GUIs should list the parameters before and after modification, and indicate the amount of change, so that changes in specifications can be compared.
But such modifications would require a significant amount of work. Since we are based on the standard GUI, adding features that do not exist in the standard can be very restrictive.
Another patch improvement that I happened to work on might slightly improve this problem.
Mouse over the vehicle you want to upgrade with that patch
1) Location of vehicle to be upgraded (This feature was recently added)
2) continuously upgraded vehicles automatically,
3) Coupling constraint error between upgraded vehicles and existing vehicles
4) Number of vehicles which is upgraded at the same time
is displayed.
(´・ω・`)ごろうじて? Check this out?

If the vehicle to be remodeled can be connected to the next vehicle, it will be displayed in purple. If an error occurs in the constraint, it will be displayed in red.
Well, it may be a little difficult to distinguish between purple and red. But it is common throughout the GUI. (´・ω・`)
Let's check another example

The convoy has only two vehicles, but upgrades have seven options.
I checked them one by one in that animation GIF. You can see that the third option does not cause any problems.
In the image, when the third option was selected, the color bar of the 2nd vehicle of convoy was displayed in purple. This indicates that the 2nd vehicle will be upgraded at the same time.
After performing the third option, one new upgrade option appears. Let's check this.
You can see that this is an upgrade that destroys the current convoy.
This seems to be a trap that traps the noob that is common in RPG games.
So you need to look into this upgradeable vehicle and do it.
Such upgrades should be avoided if you are not a geek.
Anyway, this patch will allow newbie to avoid such traps.
But we must note that this is far from the best.
For example, when upgrading A1 A2 A3 A4 to B1 B2 B3 B4, if the concatenation of group A and group B is not compatible and they are not the only combination, this improvement cannot determine if the upgrade is correct .