If you’re wondering why are there some restrictions on the maximum months duration for certain formats, in a single volume, it’s basically due to managing the maximum ‘thickness’ of the product.
Thickness relates directly to the number of pages in the diary or journal and the maximum workable thickness equates to just under 400 pages.
Therefore a 12-month Day-to-page format diary is restricted to 12 months maximum duration (365-6 pages plus additional information and notes pages). Likewise a Day across 2 pages format is restricted to 6 months maximum, resulting in the same number of pages.
In reality the great news is that you can cover as many continuous months as you wish because, only with Toad Diaries, can you choose the start and end months. For example, if you have, say, an 18-month Day-to-page requirement it can be achieved by having two separate 9-month diaries with start and end months running continuously (or indeed one 12month and one 6 month or any relevant combination in between).
At the other end of the scale, weekly and monthly formats can easily accommodate up 36 months duration as the thickness problem is not encountered due to the lower overall page-count.