Help me if I am lost in the changes. It was my understanding that miles earned as a total had an expiration of X-amount of months after activity. Looking at my statement, it does not reflect such:

YTD Elite Qualifying Points 99,768
YTD Elite Qualifying Miles 66,843
YTD Elite Qualifying Segments 26
Miles with Expiration Deferred Through 02.12.2012 153,151


So I flew last time May 26th, but my miles expire next year February? Come on...
Could it be the reason that I burnt 400,000 miles on a couple of award tickets
for family coming over in July or what sets back my expiration as quoted on my statement?