900HP - AF and ED commands - ED returns only 25 results - AF has 64 channels

900HP - AF and ED commands:
ATAF returns the bit field for 64 channels.
ATED returns only 25 results.
I have written software that reads the ‘interference’ on the original 2.4 device and have changed that code to the 900HP. When running that software, (commands converted), the ED command only returns 25 results. The software displays the interference for each channel so that a suitable channel can be selected, or so that we may be able to identify other devices that might be causing us problems and selectively mask that channel out.
Why is the ED command only returning 25 results rather than all of the available (or at least the CM frequencies). If only returning 25; what are the 25 results?
Thanks in advance.