I just had an email exchange with the service manager at my dealership after pestering him two months ago about the rumored 814 firmware upgrade and it is now available for our cars as of last week for those that are as eager as I am about keeping their MMI up-to-date as much as possible. :-D.
The official line of what it fixes is only "navigation location inaccurate or navigation takes very long time to load ", but the word on the street is that it fixes Bluetooth issues with newer OS versions such as Windows Phone 8.1, which is the main reason I want it. The prior version to that was 733, which I have now, so there's got to be more in it to warrant the jump in version/build number. I have an appointment for Tuesday to get it installed. Will report back after that.
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