Since the weekend is coming, perhaps you would like to prepare your envelopes and postcards for another nice date!
It has been a long time since we get a sequential numbered date. 04 March 2021 is possible on the small cancellation. The date will appear as 4.3.21 (4321).
Unique? Check your local post office it is a small cancellation? If yes, why not register a letter to yourself for the fun of it?