This is the hint.
This is the sixth volume of Times2 Jumbo crosswords from the long-running series in The Times, collecting together the sixty puzzles originally published between August 2007 and August 2008. I’ve done a minimum of editing, usually in an attempt to improve clarity and eliminate where I can a few recurring answers more obvious now the puzzles appear together, and they should present solvers with just the same level of challenge as the puzzles currently being published in the paper.
Unusually, one of the puzzles is mildly thematic. Noticing the approach of the cryptic puzzle numbered 747, I suggested to Richard Browne, the Editor of the Times Cryptic puzzles, that we might somehow mark the arrival of the number widely familiar from Boeing’s jumbo jet. Accordingly, I composed both the Cryptic and the Times2 Jumbos that Saturday, the former featuring a number of elephant-related answers and the Times2 with a good selection of airliner names from earlier years of aviation, before aircraft manufacturers gravitated towards more numeric designations. Several hawk-eyed solvers noted this on the day, but I won’t spoil your solving fun by pointing out which of these puzzles it is. What no one seems to have noticed was that I had made sure the two numerically appropriate entries at 7 and 47 down were the same in each puzzle and referred to the original inspiration for the idea.
Once again, most of the puzzles are by my own hand but there are also three here by Richard Browne and two each from Dave Crossland (who also proof-read this volume) and Don Manley, which were the extra puzzles published on bank holidays.
I do hope you enjoy this further generous helping of Jumbos and have many hours of good solving in tackling the puzzles.