Thank you for bringing this interesting piece to discuss.
The date is without a doubt 1778, and maker is almost certainly William Cattrell.
See marks from another spoon attributed to William Cattrell with a clear date letter of 1778.
You can see that both "WC" marks have:
- The same distinct notches in the outline over the "C"
- The same slope and notch in the outline to the left of the "W"
The WC mark on the other spoon has clearly been stamped overtop of another maker mark.
On your spoon, what you thought might be an additional letter is probably part of another maker's mark underneath.
It's difficult to see in your image due to the glare, but it appears you can just see the tip on the curl of the "C" for 1778
