I seriously doubt that there will be any blockhouses or similar units in AAE40. It’ll just make an already-complicated game even harder to understand, without adding that much to the gameplay.
They’d be a good house rule to add, and they would better represent the Maginot Line, but I don’t think they’ll be in this game.
Blockhouse could cost 5 IPC. The fortification units had lesser men than infantry units or armour units, but heavier guns, so lets pretend it has 1 IPC-worth of infantry, 2 IPC-worth of heavy artillery, 1 IPC-worth of concrete bunker protection and 1 IPC-worth of mine-fields, anti-tank obstacles and barbed wire.
The Blockhouse could roll a die on 4 or less for hit, and take two hits like a battleship.
The Blockhouse could roll 3 dices on 3 or less for hits, and take only one hit, just to simplyfie the system, but this would also depart from the classic system.
The Blockhouse could half the attacking value, so 4 attacking infantry can only roll like 2 dices, or a tank hit on 1 only.
I’m reluctant to use these types of blockhouses in the game. I think they’re far too powerful for their cost. If they only cost 5 IPCs, they should defend on a 4 (with only 1 roll, not 3), not move, and maybe have some other special power, like boosting another unit’s defense. I don’t think I’d add them into my games, though. They just make the game more complicated and encourage stagnant defense (like infantry stack) rather than the mobile attacking that the mech inf and dive bombers help provide.