How to insert a "new page" format above a cell in a LO Calc spreadsheet?

Hi, I’m using Libreoffice, Gentoo official package.
With Calc (German language pack), running on top of Gentoo GNU/Linux (amd64, locale de_DE.UTF-8),

I’m doing a spreadsheet that has my expenses listed and I want to print them on a monthly base; one page each month (I always print just the last page).

I kept having around 59 rows on each page so it would nicely fit on page boundaries (with header and footer turned off). But today, something has gone wrong and the page boundaries didn’t fit any more, there was a whole page of offset (i.e. each page had about 63 rows). I reverted to 0.43 cm line height and deleted single (empty) rows in about five or six month’s pages to make it fit the page height, again.

Problem solved, but a nicer variant (put a “new page” command in some format cell at the top of each month) is urgently required.

Any hints/tips on this, anybody?

Thanks in advance,