My experience is with Honeywell EGPWS Mk VI...
The only altitude callouts are 500, 200, 100, 50, 40, 30, 20, 10 and the "minimus minimums" call wherever the DH bug is set.
The radio altimeter does work up to 2500. But I have no idea if that is a legal requirement, a technical limitation or just a convention.
I know some Radio Altimeter boxes are labelled 10-5000ft. Never worked with those though. Sorry.
Someone here will know...