This blocked the sale of OnePlus One phone in India until this could get resolved. OxygenOS was the answer to this. Fork of Cyanogenmod with some rebranding and a few added things.
Personally I bought the OnePlus One because it came with Cyanogen. I wasn't happy with all the added cruft in CyanogenOS, so I reflashed to Cyanogenmod soon after a stable version was available.
I'm currently using OxygenOS on my OnePlus 3, but will flash to Cyanogenmod eventually to run more bleeding edge and get some features back that I miss.
This shouldn't effect OnePlus 3 as they terminated thier agreement with Cyanogen Inc after the India licencing problem.