so i am on Phera-plex right now, after my 4 weks of being on i'll be running PCT. now my question is. i am seeing great gains off this and i was considering changing my routine after 4 weeks. but now i'm debating on keeping it the same because of my progress, for 6 weeks and changing it up mid-way through PCT. how long do you guys go before switching it up.
also, i do...
back/bi (mon)
abs/calves (tues)
chest/tri (wed)
legs (fri)
shoulders & chest stretching and rotator cuff (sat)

i was thinking about switching up my routine to look like this (for 4 weeks after i decide on when to switch it up)

back/tri (mon)
shoulder & chest stretching and rotator cuff (tues)
legs (wed)
chest/bi (fri)
abs/calves (sat)

what do you guys think? i've never done the (back/tri) or (chest/bi) split before and i want to give it a try. how many of you guys have experimented with it and had good results? lastly, is there enough rest between my tri and chest workouts? i think i'll be ok but i'm just wanting input from my brothas...