A text box or object can only be on one page.
You could insert a manual page break (Ctrl+Enter) and then insert a large blank borderless textbox (at least half a page) on the new second page, then delete the page break.

Be careful of your "Keep with next" and "Keep lines together" paragraph formatting or you could end up with an orphan signature block or the like at the top of your second page.


[Edit: See Paul Edstein's post following for a much more elegant idea.]