Upgrade from 2.5.6 -> 2.7.x: Severe performance drop


I updated my chart library version from 2.5.6 -> 2.7.x and have seen a significant drop in performance. I am running on iOS 7.1.2 on an iPad Air.  Performance with 13 series and 4K points dropped from 60fps to 23fps, and on an iPad 2 it dropped from 20fps to 4fps.  I have tried removing all custom styling, custom data points, etc. and no appreciable increase in speed has been noticed.  I even reduced my series to 1 and still only got 10fps more out of it.

This is very disappointing.  What can I do to restore speed to my charts???