Since formal academia moves slower than the "jailbreak scene," the definitive papers on this are hosted in security archives.
Yes, but updating normally will trigger iCloud lock. Use Legacy iOS Kit to restore to 9.3.5 without losing bypass ability (complex). Easier: Stay on current OS if possible. Ipad 2 9.3.5 Icloud Bypass Untethered
. If you downgrade to older versions like iOS 6.1.3, the activation lock may re-trigger depending on the bypass method used. : Always download tools like Since formal academia moves slower than the "jailbreak