Just as in 2013 and 2014, 2019 will have TWO Bye weeks.

It's very simple folks, CFB season begins the Saturday before Labor day (1st Monday in September) and ends the Saturday after Thanksgiving (the 4th Thursday in November).  Then, of course, it's the post season (insert joke about lesser teams here).

In for 14 Saturdays to elapse in these start/stop weeks.

This can only happen IF August 30th or 31st is a Saturday.  In this case, Labor Day occurs on September 1st or 2nd.

If August 29th is a Saturday, the following Monday is August 31, hence labor day occurs on September 7th (opening day Saturday Sept 5th).  (ie 2015)
Basically, it's a common calendar occurance; we're just not accustom to it because before 2010 OSU and Michigan was held prior to Thanksgiving.  But, as we know seasons have been expanded.  As recent as 2005, OSU only had 11 regular season games.

So, when will there be an extra Bye week?  See, each year a specific day is pushed up to the next day of the week (ie, Aug 31, 2018 was a Friday, but a Saturday in 2019), except on leap years when there's an extra day (ie, Aug 31, 2019 was a Saturday, But will be a Monday in 2020).
There's actually a weird calendar formula, it repeats in a 27 year cycle every 11, 6, 5, and 6 years.  So, going from 2013 (Aug 30 a Saturday) and 2014 (Aug 31 a Saturday), let's extrapolate out to 2100, a mere 80 years after Justin Fields goes pro.

I could go on beyond 2100, but my CFB forecasts start to get cloudy.  That's when the 2096 recruits have their senior days, and, hopefully, have 3 pins of golden pants in their lockers (as is tradition these days).  
Hopefully 11W is still around to tell the future Buckeyes (may this article live on their servers until then, and beyond) :)