I had the right idea pretty quickly! But I was making a small mistake... But as it always goes for this game, any mistake means you fall short! For me, this was less of a sneaky puzzle and more of a 'are you making any mistakes?' puzzle.
Wow, the first time I set a new record. Since no one has beaten it (technically), it's now an SGM - but I still consider this PhD level... But now I wonder if it will be pushed further?