I'VE GOT IT! You need to press ALT and F11 after opening the debug toolbar.
Okay so I was in the VAB earlier, and I was about to build a rocket when I press ALT F12 for sciency stuff, and then this pops up.
Below the normal list of cheats you normally find, a bunch of new options popped up, including add to/remove science, funds and rep. The other options allowed for use of stock vesels, maximize research and unlock all parts, give all crew max experience, max facility (upgrade to lvl 3) and max progress (seems to not work, might be for a later update)
This only rarely appears as I've tested it, and you need to have it open for a bit and I think you need to hover your mouse over a button to unlock the new menu, otherwise it will have the normal list of cheats you'd usually find.