my friend has the bionic and got the update Monday night, she was dropping data signals by the next day. we tried everything, airplane mode on/off, battery pulls, uninstalled all apps, factory reset, new sim, cleared history/cache/cookies and everything else mentioned here (I had 3 bionics myself) but it is still dropping.
what prompted the new SIM was her attempt to return the phone but wasoutside the return period...rep stated between the update and SIM, it would resolve the data dropping, but 20 minutes after leaving the store it dropped, which led to the factory reset.
By the way...the high pitch still exist.
I had success with "almost" getting rid of the drops by shutting down my bionic, removing the sim card, rebooting the phone (without the card), it will boot up and say "install sim card" or something to that effect, power down phone again, reinstall the sim card, boot up again, let it do all of its "boot up stuff" and then roll with it. I've only had to do this once and I was getting a ton of data drops before, in the neighborhood of 5-6 daily. I hope this helps.
we tried the trick mentioned above, we turned off the phone, took out the SIM, powered the phone back on without the SIM, allowed it to boot completely, turned it off, put SIM back in then powered back on...we were amazed for the rest of that day (about 10 hours) the data did not drop once!
today, its dropping again like crazy...goodbye Bionic! i told her NOT to get this phone, now she has to buy a new one since every trick in the book + .893 did nothing.