Is a 16-day Apple Beta Review time normal?
No, this is not a normal review time.

Review Times

You can get a gauge of average App Store review times on http://appreviewtimes.com


  This site tracks the average App Store review times for both the iOS and the Mac App Store using data crowdsourced from iOS and Mac developers.


The current average iOS review time is 2 days.

Having submitted an expedited beta review, there is nothing you can officially do but wait. As a developer, the review process can feel capricious.