I just tried,
date_create_from_format(\'Ym\',\'201302\')
And I guess because it\'s the 29th today, it\'s actually giving me back March 1st.
TheWolf's solution seems to work perfectly, but here's an alternative I started writing anyway:
function CompactStrToTime($str) {
$year = strlen($str)>=4 ? substr($str,0,4) : date('Y');
$month = strlen($str)>=6 ? substr($str,4,2) : 1;
$day = strlen($str)>=8 ? substr($str,6,2) : 1;
$hour = strlen($str)>=10 ? substr($str,8,2) : 0;
$min = strlen($str)>=12 ? substr($str,10,2) : 0;
$sec = strlen($str)>=14 ? substr($str,12,2) : 0;
return mktime($hour,$min,$sec,$month,$day,$year);
}