Did a little more research, and it seems as if you can switch back. Some had problems, but the posts I found were 2014-2015. I'd probably make a TWRP backup first. The only thing I am not sure if it will work is Xposed. I may try this bit want to wait for a few more replies to see what others have experienced.
TY
I would definitely make a TWRP backup, Xposed has messed up a few of my devices. I would stick with the runtime the phone comes with, as its probably the best preforming one on lollipop and under.