Insert/Type/Paste CAPITALIZED weekday name (and YESTERDAY's weekday)

I'm able to use a key sequence trigger to enter some text, and have the current date entered showing the weekday name. Great start! But I want it in ALL-CAPS.

Using this: (BTT)@dateformat:EEEE MM/dd/YYYY(BTT)
Produces this: Wednesday 04/08/2020

I want it to look like this: WEDNESDAY 04/08/2020
Or just: WEDNESDAY
(because I can append the rest easily)

How to do that?

Also,related so I'm including in same topic though somewhat different question, in the same text entry I want to include The PRIOR day's name.

So on the day above it would produce: TUESDAY

(Being able to product 04/07/2020 would be great too but not required)

If a script or terminal activity is required, I'd really appreciate specifics.
Thanks much