Doing OTA directly over .62 gave me a failure too. Here's what I did- flashed stock .42, root (and updated the SU app and binary and ticked 'OTA Survival', updated to .84 via OTA.. Success. Feels li'l bit snappier and ya battery stays up good. But maybe it's jst a placebo cuz GB has always hav been snappy n fast on my mini.
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