IMO, I would not renew the Kaplan course. While the CATs are beneficial, if you have taken most of them you will start to see mostly repeats. The UPT is a good thing to do, even if you aren't scoring where you want. You should take it before the access expires.
For my personal experience, I took the full blown Kaplan course- ended up scoring a 650 on the actual GMAT. I took advantage of the "unsatisfied" policy that they have, and renewed the online resources. I used these materials up to my next GMAT, where I only scored 660. After these Kaplan resources expired, I tired a more thorough approach to studying.
Using the
GMAT club tests, Manhattan Quant, all of the OGs, and studying the Manhattan SC and powerscore CR Bible books gave me a much better review of the concepts needed to really see improvement in the score. You will have PLENTY of CATs/practice left to work with - through
MGMAT, GMAT club, and GMAT Prep.
After using these resources over a 2 month or so period, I got a 710. I wish I had known about the above mentioned materials in the first place!