If you read carefully, you'll see I wrote that 6 months is a good number to start with. It all depends on how much risk a country wants to take to run out (or needing to buy energy at extremely high prices). These lessons are not coming from a very distant past. There is more than just consumption. Again: you'll need to replenish and store strategically or suffer the consequences. Your assumption doesn't include any strategic decission making.
Well, for one I want to note that you are kinda changing the topic. The context that I was responding to above was tszaboo creating the impression that we would need to store enough energy to meet demand for 6 months from storage alone just so we don't suffer blackouts because there is supposedly close to no local renewable production during the winter. So, strategic reserves were not really the topic and would be on top of that.
Also, while some strategic reserves certainly make sense, it should be noted that the problem we just experienced was a of lack of storage (because the largest storage facility in Germany had been sold to Russia, who, in preparation for the war, had let it run empty) combined with a lack of import capacity from sources other than Russia. Removing either factor should have considerably reduced the impact.
On top of that, local production will be far less than you seem to assume. I don't recall Germany has their own (significant) oil supply and yet the energy coming from that oil will need to be replaced by a different energy source at some point.
It's just ... no, it doesn't. Much of the oil supply goes to mobility, cars in particular. ICEs in cars have an efficiency of around 20%, maybe 30% (depends on how the car is being used). Electric cars have an efficiency of ~ 65 to 80% (depending on which parts of the process you include, charging losses in particular). So, about two thirds of the energy that we import in the form of oil for the use in cars does not need to be replaced, because it is currently only used to heat the environment, and we can stop doing that. Equally, energy from oil that is used for heating homes can be substituted with roughly a third of that in the form of electricity that is used to drive heat pumps, which then extract the remaining 60 to 70% from the environment to create the same amount of heat. And with some insulation, you can potentially further reduce the amount of heat energy that you need in the first place.
How much exactly we need to replace is ultimately an economic question (i.e., whether it is cheaper to insulate a home or to import hydrogen, or whatever), but we certainly don't need to replace anywhere near the energy content of the fossil fuels that we currently import with renewable sources.
(Of course, you can then argue whether a heat pump reduces the energy demand or whether it should be considered a renewable power plant ... regardless, the point stands that you don't need to replace oil or natural gas used for heating with the equivalent amount of renewable electricity.)