iOS 10.2.1 was publicly released on 1/23/17 (yessterday) with under-the-hood improvements - including a security fix - and several accessibility updates. According to AppleVis it appears that the pairing issue with Freedom Scientific's Focus Blue braille display and several other braille displays has been resolved. Also, when typing in any text field with a braille display, the text input is no longer sluggish. AppleVis stresses that while they are not aware of other accessibility changes, regressions or improvements, it is impossible to test all devices, apps and scenarios, especially with a very recent software update. Power users in several iOS groups are stating that iOS 10.2.1 is working well for them.