The note relating to the re-designation of 4 LofC as 8th Army Signals in 1942 is not reflected in the 4 LofC diaries in that, at Kew at least, there are 4 LofC diaries beyond those I cited earlier, going on to 1945 in fact.
The whole list, 19 diaries (although there is some overlap where company diaries exist) is at the link:
http://www.rootschat.com/links/01o13/ I note that the titles from about 1943 don't have "Italy" in the title which is usually the case when a unit, previously in N Africa, moves to Italy (as we know George did). I would be happier if the diary covering the July 1942 period confirmed the change of unit title and if we saw the move to Italy reflected in the diaries from late 1943.
Thus if you wish to find detail of where the unit was operating during those three years, I'd recommend a check of the two mentioned above to be sure about the unit. (I should have said that there are no diaries entitled "8th Army Signals" or indeed, apart from a couple of military police ones, none with 8th Army in the title at all).
Quite a lot of documentation to go through. I should let you think about how you wish to go about it from here on.
MaxD
PS Ignore the attachment if it opens, tried to delete it!