Having a look at the 1st Guards Brigade war diary at TNA; I was rather saddened to see that the entire diary had been torn out leaving only a few pages. It hadn't fallen out; it had been ripped out, intentionally from every single month (a number of seperate folders) for the combat in 1943 leaving only a solitary page. This might not have been vandalism; it could be that the pages were taken out for official use and never put back: but I was wondering if another copy exists in the worls or if that is it for those months (the entire tunisian conflict)? I informed TNA but it was very dissapointing given that the 2nd Guards I'm researching didn't use map references in nov/Dec '42 and I'm now going to have to go to the divisional level and hope for the best.
its something I've noticed before, sometimes days, weeks or months are just not there. Like you mention, it could be that they were used for official reasons and not replaced, or it might be that sensitive sections were taken out deliberately for some reason