The majority of the programs on this site are intended for people who have no muscular embalances unless specified.
If I were you and had a lagging body part, I would only do maintenance work on it's antagonist. So for you, you say that your chest is lagging, therefore I would suggest excluding the chest and upper/middle back from the routine you're on, for now, if possible and supplement a routine where you would be giving your chest more work than your upper/middle back.
(Now, I'm not familiar with the program you're on--so you're going to need to check and see if it would fit)
Bench Press 3x8
Barbell Row 3x12
Bench Press 5x5
It's just an example, now of course you just wouldn't want to do 3x12 for your back all week, if you don't get what I'm going for (a 2 to 1 ratio), PM me.