Looks the same as the 241 cups I've got. There's a half-circle 'lip' on the back of the mount, with your thumb around pin, use your forefinger under this lip and pull up to release the vacuum pressure.
I do not have those cups, but there is a raised section on the side of the rubber foot, a little tug on that away from what it is stuck to, should lift away with no issues
lmao did you stay at work for the hour trying?