This is one of those little oddities that nobody can explain, but which hold considerable value to collectors.

Between 1967 and 1969, from when the album was first issued until the 'Sold in UK' statement was removed, there was an incident at the EMI pressing plant that was at the time dealing with the Sgt. Pepper LP. I have compared a standard label to a non ADitL label and the typeset is identical, so to me it doesn't look like it was a mistake during a fiddle with the label printer plates. Also, because the credit text underneath the song titles has been moved up to compensate for the gap left by the omission of the ADitL, it can't have been a printing error where that particular line, for some reason, was not printed onto the label.

The song itself still appears on the disc.

People can only speculate as to what could have caused it. One reason may be that the original typeset printer plates were beginning to wear and, as was typical of the vinyl pressing plates, were replaced and re-set. However, maybe because of a typesheet that contained an error, or because the engineer misread his notes, the song 'A Day in the Life' was accidentally omitted. Another more comical yet much less likely possibility was that one of the workers at the plant deeply hated that particular song, and in a move of spite, malice or perhaps as some kind of joke, intentionally took the song credit out of the typeset plates. If this did actually happen then I very much doubt he'd have kept his job upon its discovery!

Whatever the reason, copies that omit 'A Day in the Life' on the side 2 label are incredibly hard to find and are in huge demand from collectors.