I think I found a little hack you could use
Array.Push(YourValue) // push a new element regardless of the comparison
Array.Delete(Array.At(Array.Width-2) = Array.At(Array.Width-1) ? Array.Width-1 : Array.Width) // compare and delete if need be
I might have screwed that up, but essentially you can exploit the fact that trying to delete an element outside of the array does NOTHING. So you can put your conditional in the delete event. If the comparison passes, use an index outside the array (so it won't delete anything). If it fails, then delete the element you just added by using the last index in the array.