303 - 44 (17 days of combat) - 2.59 kills per day
17 days? Can you perhaps explain why Josef František, 303 squadron's leading ace in the Battle of Britain had his first BoB kill on 2 September and the battle lasted until 31 October? In fact, all of František's BoB victories came between 2 September and 30 September and he wasn't even alive for the final 17 days of the battle. Oops, you appear to have been caught lying yet again.
Further proof that you are lying comes from the Operations Record Book of the No.303 Squadron, August 1940, F540 (NA AIR 27/1663).
It is available here and it clearly shows the first combat as being on 30 August 1940.
Do you mean to claim that 303 Squadron was then fighting a battle other than the battle of Britain? Which battle was that?
And let's have a look at some of your other numbers. According to you, 603 squadron had 59 days of combat in which it got its 57 kills but 303 had just 17 days. However, 603 squadron was based in Scotland until 27 August 1940 and didn't see its first BoB combat until 28 August 1940. Oops again.
So lets subtract non Polish scores and then let's get insanely wild and assume that kills by all 4 non-Polish pilots within 303 were 50% of all confirmed kills by 303.
Alternatively, let's just look at the figures:
# Sqn Ldr R G Kellett DSO DFC Original CO of 303 Sqn during the Battle of Britain, (five claims)
# Flt Lt John A. Kent, Canadian Flight commander during the Battle, (11 claims)
# Sgt Josef František, Czech Sgt. pilot flying with 303 Polish Squadron, was the one of the top fighter pilots of the Battle of Britain, with 17 confirmed kills.
44 kills you said?