Do you have any flights booked after February 28th? You may be given a goodwill promotion to gold if it's only 125 miles, but don't rely on it. However do remember that not all of your tier miles "expire" at once on the date of the end of your silver status - it will go back to checking the previous 13 months on a rolling monthly basis, so if you have 0 miles earnt in Feb 2014 and a flight booked in March 2015 you'll make gold.