Leader (2 cycles): less intensive work on main lift (e.g., 5s pro), higher volume supplemental (e.g., BBS, SSL), lower volume assistance
Anchor (1 cycle): higher intensity on main work (e.g., PR set, Jokers), less supplemental work (nothing, FSL), higher volume of easy assistance
TM testing between and at the end. Conditioning tailored to what you need.
Concept is simple. Like in many training approaches, you're moving from a higher volume, less intense base block to a higher intensity block. Just different terminology.