More nice FoW stuff, and this time about the Brits and their Empire.
As a Canadian player, this warms my heart.

Again, there are a few mistakes, though.

First off, British Infantry lists can’t always use Night Attack. They can only do so in scenarios without the “Meeting Engagement” rule. So, you can’t Night Attack in Free-for-All, Encounter or Dust Up.
This is because a night assault needs some preparation and these missions represent forces coincidentally running into each other.

One notable thing about viewing range at night is that, for artillery, it’s the observer’s viewing range that matters.

Moving and assaulting with infanty from 14″ away: nope, can’t do that. After moving normally (6″) and your assault move (4″ for a total of 10″) at least one of your teams must be able to reach base-to-base contact with an enemy team to assault.
Do note that you can mark the position of any enemy team you destroy in the Shooting Step. You can still assault those abandoned positions as if they were occupied that turn.

Allocating hits and removing casualties from shooting/assault attacks is something that you’ve been doing wrong for some time now. You need to allocate all hits scored evenly across the various teams that could be hit by thost attacks. For most shooting, ranges are long enough for any hit to be allocated to any team in the target platoon, but with things like SMGs (4″/10cm range) or Assault attacks (2″/5cm range) it becomes really important that only teams within range can have hits allocated.
This means the second line of an assaulted platoon often can’t even be hurt in the initial round of attacks.
Once all hits from the shooting/attacking platoon have been allocated, roll saves (if needed) individually for each team that had hits allocated to it. Some teams might take multiple hits and fail multiple saves, so this is important for the number of casualties you take.

This failure in hit allocation and casualty removal has a massive effect on how you’d use these Wasps here. With only 3 teams within the 4″/10cm range (so only 3 teams that could be killed), I’d only shoot with one or two of the Carriers and save the flamethrower fuel in the other(s) for later turns if needed. Their primarly role isn’t to kill the entire enemy platoon anyway. They just provide almost-guaranteed pinning for the following assault by the infantry.
Also note that the Wasps themselves can’t assault, since they’re armed with flamethrowers (and are not Russians).
Also, you don’t -have- to remove empty flame-thrower vehicles, although you can if you want to. Some of them (like Churchill Crocodiles) do have other weapons, after all.

All in all, night fighting is often an excellent way to go on the offensive as a British player, but a properly set-up defensive position with artillery support and the like can still mess up an attack like this by taking out key elements or delaying it until it’s light again.