Sorry Ed, but I have to disagree. In working with 321 ss, cold working this material will reduce elevated temperature mechanical properties. This is part of the reason why we established formability limits in ASME Section I, PG-19.
If you cold work in excess of 15% strain AND have exposure to service temperatures between 1000-1250 deg F, or exposure to service temperatures above 1250 deg F AND 10% strain we had instituted requirements for a post fabrication anneal. I would follow these requirements if the coil is eposed to service temperatures above 1000 deg F.