Seems this conundrum creates a lot of misunderstanding.
As I have seen an air battle as well as a ground battle can be the most contested battle.
I think what happens is that some people see their air battle is most contested and then check whether there are air battles of the same damage whilst I think both air and ground are compared using some kind of scale.
Anyway dont think one can trust scripts and that rather use the filter as your battle is closing to see if it is still listed as epic.
In short use the game to check whether something in the game is true not some kind of script which obviously can have delays between actual game andscript info.
if I'm incorrect please explain.