Got mine done this morning ... just under 2 hours. Looks much smoother transitioning from one screen to another. Tested the phone, headset, Nav6, turn by turn on board GPS on TFT and streamed Spotify via the TFT connectivity... all working perfectly. With the TFT GPS instructions, the music volume is lowered when the voice command comes on. Previously the music will just mute when the voice command came on. The fuel range used to hover around 450km on a full tank. Now it's actually showing closer to the true mileage on a full tank. There is also a new little symbol on the bottom of TFT to show that the DRL is set on auto and it goes off when the main light comes on. Of course, when you power up ABS Pro comes up on bottom of screen.
However, after the update all Bluetooth connected devices were reset but pairing the phone and my Sena 20s was just a matter of seconds.
I asked why BMW is requesting all TFT to be updated and was told the previous firmware had errors showing up on the diagnostics due to some bugs.
Hopefully, it will be happy days from now although I didn't have any issues with my previous firmware version. Great service from the BMW dealer and especially the guys who are on the ground.