Similar to GWR, which is 20/20 (20mph at 200m from the signal, stopping 20m from the signal) or 10/20 in low adhesion (10mph 200m from the signal, stopping 20m from the signal). So no reference to AWS magnets.
It's not so much that the magnet can be at an incorrect distance, it's more that there is an assumption that all magnets are 200yds/183m from the signal when the current standard specifies that the magnet is placed 'at a distance that equates to at least three seconds train running time, calculated at the maximum permissible speed applicable at the AWS track equipment' (see 3.1.7 of RIS-0775-CCS). That means that where linespeed is 30mph (for example), the AWS magnet can be placed 40m from the signal (assuming I've got my distance/speed/time triangle correct!).