Double Dipping in Catch of The Day Uni Day's Discount, Paid $19.40 for Legend of Zelda on Switch

Hey Guys,

I just managed to somehow find a loophole in Catch's operations. So I purchased $200 worth of Catch vouchers a while back for 20% off. I used that in conjunction with the 10% Unidays discount to purchase a Switch and MarioKart. (Totaling roughly $386.60 Delivered) I was pretty happy with that, however, the next day I gave in and decided I wanted Zelda as well. I got in contact with support and asked if it was too late to add the game as it hadn't shipped yet. She said it was too late but what she offered to do instead is where I find my loophole.

She offered to cancel the order and give me a store credit on the full worth of the switch and Mario Kart game. ($472.94 including what I paid for shipping) I then went and re-added the switch and game plus Zelda as well. Then from there, I added a new Unidays 10% discount code and to my surprise, it worked! So I paid $19.40 for The Legend of Zelda!

Link to see my cart at checkout:
https://ibb.co/f2i668

I get the feeling I am a unique case but it wouldn't hurt to try the same thing :)