Not an expert on this but my understanding is that at 2+ risk starts to increase, especially that have seen high use and fast charging. My layman understand is

Not an expert on this but my understanding is that at 2+ risk starts to increase, especially that have seen high use and fast charging. My layman understand is that dendrites accumulate over time so risk is incremental over use...and for phones use and time is basically same thing. Low use items I'd totally run for many more years.