r.MobileReduceLoadedMips can not work on android?

hi, i use Unreal Engine 4.16, i try to use r.MobileReduceLoadedMips on android, but it seem not work correct. in the code UTexture2D::CreateResource, “RequestedMips” be modify to [MinAllowedMips, MaxAllowedMips], but it always equal to “NumMips”.

is it can use on android? if it can, how to use it?