Unless you are like our friend and proud Dad, Mr. Pear, and turn off everything on your phone and disconnect from all radios overnight, a 1% drop per hour is not to be unexpected. That implies nearly 4 days of standby time. Now if you’re losing 4-5% per hour, then there might be an issue. But its only been 18 hours since it was released, so, at least for last night, the issue might be re-indexing and the other processes that go on after an update.
See how it does tonight before reaching the conclusion that there might be a problem.