Yeah, but in case of that, every position has a fixed height. I'm not sure, if this is a solution which will work.
A other way would be, that you count the lines in summary and then divide it trough a fixed line-count.
Example:
First-page got 30 lines
Second got 50 lines
While processing and printing the positions you count your lines
1st pos 10 lines
2nd pos 14 lines
3rd pos 19 lines
4th pos 11 lines
~~~~~~~~~~~~~~
5 pos = 54lines - 30(possible lines first page) = 24 left on second
But that means, no protect used, you know before, how many lines a position got and that is a lot of preconditions I'm not sure if is to deliver like that... Would be a great bucket of work and in case of that, I'm not sure if it takes more time to get a clue through the otf-data and that for sure, if yare one time into it gives a lot of new possibilities...
~Florian