I only upgraded from a OnePlus 3T to a 6T because the former got stolen. I hope LineageOS becomes stable enough on the 6T so that I can keep using an Android OS with recent security patches, but like most phones, the battery will probably be the first thing to give up.
Many of my earlier smartphones had batteries that were easily replaced. The 6T requires special tools, among them a heat gun to soften the glue on the back cover. And ifixit says that's "moderate difficulty".
Many of my earlier smartphones had batteries that were easily replaced. The 6T requires special tools, among them a heat gun to soften the glue on the back cover. And ifixit says that's "moderate difficulty".