Simply put: How did Finland prepare for its Continuation War? Other than having 250.000 German “tourists” in the Lapland. Was the Finnish high-ups expecting a swift German victory or did they have more realistic expectations of the upcoming war?
First to make it clear - Finnish preparations for most parts were for the presumed ‘second round’ but they were done or started already at the time when there was no inkling of the operation Barbarossa.
Sizable amount of war material had been shipped towards Finland during the Winter War, but plenty of it didn’t arrive in time. Furthermore the Germans interned quite a bit of it. As the relations with the Germans started to thaw the Germans released the interned shipments which considerably helped the Finnish situation. However Finland was really worried with the intentions of the USSR and assumed that renewed invasion was just a question of time (Molotov’s later comments in November seem to confirm this). So the Finns were desperate for any allies, equipment or help they could get.
Germans offered a deal. To have allow German troops to transit through Finland to northern Norway. They would need to have depots and some limited amount of troops in the area as well (which given the distance and lack of infrastructure was not actually unreasonable request). From the Finnish point of view it was a great thing since it was perceived (correctly) that even a minor German presence would act as a shield against the Soviet pressure. And despite of other political consequences what Finns really, really needed was a shield against that pressure. Later some of the Germans called it the ‘Fuhrer’s umbrella’. In exchange for the transit rights the Germans would start trading with Finland. This trade included weapons - Germans were willing to sell some of the equipment they had captured.
These new (well, “recently delivered” might be more accurate as very few of them were ‘state of the art’) weapons, large amounts of captured Soviet equipment, extended conscription period, continuing state of war and other means allowed expanding the Finnish military quite a bit. And more importantly it could now be armed far better than what it had been in 1939 while having much greater amount of supplies available for it.
Finland largely expected a swift German victory. Like most of the world did. The excessive mobilization rate that could not really be sustained could be seen as an indication of this. However there doesn’t appear to have been much plans beyond that. What Finns expected to gain or what they expected to happen afterwards is very hard to determine. Problem for Finland - which was recognized by the leadership - was that Finland was not actually all that pro-German (more like anglophile) and should the USSR be done with the Germans could overcome Finland with relative ease. Which lead to some one commenting that what Finns needed was a miracle - (roughly on the lines) that what the Finns needed was that the Germans would beat the Soviets and that afterwards the Allies would beat the Germans.