MagazineWith the ever-changing airline industry, your miles may not be there when youneed them Alexis McCombsJune 1, 2006December 1, 2008 0 valign=”top”>activity every 36 months 8,000-15,000 miles to upgrade (one-way) Continental/OnePass www.continental.com More than 70 500+ None 25,000 miles w/in the U.S. & Canada  28 airlines   15,000 miles to upgrade (one-way) Delta/SkyMiles www.delta.com More than 90 900+ None as long as there is 25,000 miles w/in U.S. & Canada  19 airlines  36 months 5,000-10,000 miles to 36 months upgrade (one-way) *Restrictions may apply. See Websites for more information. For more information, log on to www.InsideFlyer.com or www.Smarter Travel.com. 1 2