Miles From Our Home: 2018 Canada ISOTed to December 1939

  Its a point but I doubt they expect an attack from the US and there's no one else who could get anywhere near them.

  If the Germans are still stupid enough to go with the OTL plan then they can do a hell of a lot.  While modern munitions last they can smash German concentrations with a lot of firepower, especially since AGA [Army Group A] is going to be concentrated in a pretty small area.  When the modern stuff is gone they can use down-time dumb weapons, made more efficient by their modern targeting, high speed and altitude which makes interception far more difficult.  This can be boosted if you can start adding methods to increase the accuracy of the down-time weapons, say fin stablised bombs.  If that's not practical they can be used for scouting operations, identifying German positions and movements.  That in itself would be a huge boost for the allies.

  The down-timers would be able to very effectively counter much of the German attack.  Once they realise the Germans haven't changed their plans they can boost the forces dug in at places like Sedan, which will be markedly larger and better equipped than OTL and the Germans will be making frontal assaults on powerful defences.  Relatively light forces operating in the Ardennes - which might be all that's available depending on how much Belgium is able/willing to relax its neutrality can slow things down a bit and give info on the size and direction of the German attacks.  The big fight would probably be seeking to cross the river Meuse at Sedan where their likely to find regular troops backed by artillery and powerful air defences to minimise Luftwaffe support and quite likely allied reinforcements quickly arriving.  Here the Germans are likely to get a very bloody nose and probably make no progress at all.

  Possibly the allied might let the Germans cross at Sedan, albeit almost certainly after heavy fighting, so that the bulk of the German armour is committed to the drive to the coast can then be isolated and destroyed.  However I doubt the French especially would be willing to allow that so its only likely to happen by chance if the allies still make serious mistakes.  More likely German attacks will be lower but heavy because they will be unable to drive across the Meuse.

  Its a bit more difficult to say what will happen with AGB as while large it has only the older, weaker Panzer I's and IIs but its facing weaker opposition who may not be as fully integrated into the allied operations because of their neutrality and the allied need for intelligence security as well as possibly being less willing to believe what their being told by the Canadians.  Also since they don't have a single narrow line of advance the well trained German units may be able to work around defensive positions, even with Canadian and down-time allied support for them.  However some preparations will have taken place almost certainly and a prepared allied set-up should be able to do a lot more to defeat the Luftwaffe.

  I suppose there is a possibility, although it would unlikely at this stage, that another defeat, although proportionately not as extreme as the one in Norway, could cause enough of a crisis in Germany that you could get some sort of military coup against the Nazis.  However even if this worked the German military would probably be unlikely to offer terms that would be acceptable to the allies without further conflict.

  The other thing of course, presuming they can sort out co-ordination with down-time units and reliable munitions supply is that they act as fighter cover for down-time bombers.  Wouldn't fancy being in an Me109, let alone a Me 110 trying to intercept a bombing raid and getting a flight of Hornets coming in from on high.  Could only be used to a limited degree as their few in numbers and I bet need a lot more maintenance time than a down-time fighter but likely to be able to cause Goring's boys real pain.  [Or to avoid having to co-ordinate with 1940 a/c just as quick response units to hit German air attacks.]  Do the Canadians have anything that can be used as an AWAC.  That could be very useful for both them and down-time fighter defences.