oukitel u8 Rom

Hi, i have an Oukitel U8, a chinese phone launched last year, and currently it runs Android 5.1. I would like to know if somenone knows if there are costumized roms for this phone, like cyanogen mod that runs android 6.0, i have googled it but i haven´t find anything, i would apreciate some help.
I would like to know if you know how to overclock this, just because the CPU is limited at 988Mhz per core. (quad-core)

Thank you and sry for my bad english