I've also checked the ledgers with the BSAM20 production again, and have come to this conclusion:
After the August 26th raid the production of the M20 wasn't interrupted or delayed.
This is the daily production before and after the November air raids:
1/11: 82
2/11: 49
3/11: none (Sunday)
4/11: 65
5/11: 85
6/11: 81
7/11: 82
8/11: 89
9/11: 39
10/11: none (Sunday)
11/11: 59
12/11: 59
13/11: 92
14/11: 87
15/11: 80
16/11: 50
17/11: none (Sunday)
18/11: 57
19/11: 67
20/11: 33 (this is just after the air raid of 19/11)
21/11: none
22/11: 20
From November 23rd 1940 onwards (this is just after the air raid of 22/11) the production was delayed until December 22nd 1940:
22/12: 6
23/12: none
24/12: 24
25/12: none (Christmas)
26/12: 49
27/12: 23
28/12: 53
29/12: none (Sunday)
30/12: 46
31/12: 58
1/1/1941: 24 (New Year)
2/1: 50
3/1: 46
4/1: 36
5/1: none (Sunday)
6/1: 50
7/1: 47
8/1: 52
9/1: 50
10/1: 57
etc...
The November air raids clearly had an effect on the production: not only had the production been delayed by a month, but the average production of 70 motorcycles per day had dropped to an average of only 35 bikes per day when the production resumed in late December 1940 - early January 1941. Also interesting to see that production continued on New Year's day!
Jan