That's a very good point. If I look at my android experience, two major updates is the limit I would _want_ to update to. On devices where I could push the limi

That's a very good point. If I look at my android experience, two major updates is the limit I would _want_ to update to. On devices where I could push the limits with lineage/cyanogenos, I could perhaps extend this to 3, being pretty apparent you're sacrificing speed for security at that point. I hope they're going for a different track record.