I agree with Gerenb - even with bluetooth off, I too have to kill the app in my iPhone to get the true reading upon startup.
Thanks for raising the ticket.
It seems every time apple does an iOS iupdate we have to go back and tune the network connectivity on each of the hardware platforms (gen 1, gen2, gen 3, touch, iphone, ipad) as well as the new iOS version... The multi-tasking has brought a number of subtle edge cases out, I think.
Please keep letting us know when you find these anomalies, especially if you can get it to repeat.
Thanks everyone for your continued support.