Hi, I made about 15 chicken pot pies. Homemade crust, crisco, butter, AP flour & salt. made filling the day before, so it would be completely cooled when assembling pies. Filled both crust, topped with full crust. set in freezer to harden up, egg washed them, then wrapped in foil. Opened a few up and found grayish spots all over them. Some of no spots, some have a few, some have a lot of spots. I baked one off, and the spots seem to disappear. Any ideas on what this is? I have never had this problem before. Thanks in advance!