Thank you, Garry. Accuracy is not pedantry and, moreover, it is a must in research.
The subject seems to be a bit blurred. One would expect such a serious reorganisation to have been ordered from Berlin at the identical time.
For Baden you have named a source, which I do not doubt.
Buddrus mentions 1 February 1941 (p. 1091, footnote 32) for the division of the HJ
Gebiet of Schlesien:
32 Das bisherige Gebiet Schlesien (4) wurde in Angleichung an
die Gaue der NSDAP am 1.2.1941 in die neuen Gebiete Niederschlesien
(4) und Oberschlesien (40) geteilt.
32 The previous area of Silesia (4) was divided in alignment with the
the NSDAP districts on 1.2.1941 into the new areas of Lower Silesia
(4) and Upper Silesia (40).
The creation of the two Gaue Niederschlesien and Oberschlesien had taken place on the symbolic date of 18 January 1941 (Founding of the Kingdom of Prussia 1701):
Die Gaue Niederschlesien und Oberschlesien sind mit Wirkung vom 18. Januar 1941 aus dem Gau Schlesien gebildet worden.
The Gaue Lower Silesia and Upper Silesia were formed from the Gau Silesia with effect from 18 January 1941.
Source: Wirtschaft und Statistik, 1st March issue 1941, p. 90, footnote 2.
So in this case the date of 1 January is unlikely.
However, it is also possible that this was published at the beginning of January and then executed in the middle of the month respectively at the beginning of February 1941.
This would explain why the literature on the Silesian Gau Division also contains a wide variety of dates: early 1941, January, 18 January, 1 February, etc.
As for the Bann leaders: I knew you had them