It is possible to transfer troops that are horizontal from each other and that have 1 intervening hex between them.

e.g., Hex 59,38 and 60,37 are considered adjacent to each other when transferring troops.

I expect this occurs because of old code back in the days when the map was a grid and not a hex system.

It is not possible to attack troops from one of these hexes to the other (as should be the case). It should not be possible to transfer troops either.