With the addition of concepts such as 351, 5sPRO, SST, FSL, Jokers, the various "Challenges" and newer templates etc., Jim continues to improve and evolve his system.
There now seems to be a focus on more "full body" type templates where lower and upper main lifts are combined in one workout.
However, as I approach "grey pube" territory, I have found that reverting to the "original" 531 rotation; one "main" lift per session; going for rep PRs on a regular basis but just getting the reps in on less than stellar days; usually with a Triumvirate-type template and deloading every 4th week;still produces the best results for strength.
Less volume, shorter (possibly more intense?), less "complicated" sessions and a focus on PRs still works!