Jabberwocky
Staff Sergeant
Two dates. The Day before 18.12.1940 Mid 10.1941.
Bwuh?
17-December-1940, the day before Furher Directive 21.
October 1941, the slowing of German advances outside of Moscow.
Forgive my incredulity, but neither of these two events have any effect on the "Battle of Britain" which stretched between late June and late October 1940. By December 1940, the battle has been over for a good two months.
You'd need a second offensive, either in 1941 or 1942, for the Luftwaffe to attempt again to "crush" the RAF. As I've expressed earlier, the defensive situation for the RAF, both during the day and night, was vastly better in 1941 and 1942 than it was in 1940. Both in comparative and absolute (numerical) terms.
To defeat the RAF, Germany needs to wage a battle of attrition against an opponent that is producing more aircraft and pilots than it, as well as sourcing aircraft and pilots from the Commonwealth and US. It needs to do this over its opponent's territory. Against the finest air defence network that had ever existed to that point in history. Against an opponent that beat the Luftwaffe once and is confident that it can do so again.