NB> The problem here is, it is referred to 80x25 mode. Not 80x23 or 80x24.
 NB> You should be able to use all blank spaces on an 80x25 screen without it
 NB> "scrolling up a line".

You should be, but ANSI-BBS emulation doesn't allow it sadly.

ANSI BBS auto advances to the next line after the 80th column. There is no
virtual 81st column in ANSI BBS (only in the later VT standards), so the 80th
character on the last line of the terminal screen should always cause a scroll
up if you write to it, otherwise its not behaving accurately.

 NB> The OP was wondering how to at the very least get the 24th line to
 NB> display without scrolling. I gave him a "workaround" for that, but the
 NB> workaround should not be needed, IMO.

You *could* use 80x25 if you want including 80th column on every line except
the 25th because it'll cause a scroll.  This also assumes that the client
doesn't have a 25 line being taken by a status bar, which is a bad thing to
assume in my opinion.

The safest "maximum" is to use 80x24, but only write on the 80th column on
lines 1-23, leaving the 80th on 24 alone so it doesn't cause a scroll on
80x24 terminals.

--- Mystic BBS v1.11 A3 (Windows)