I just want to point out that the method to change your time zones does indeed work, but you do not have to wait 15 minutes before you switch to the next time zone.
I started this game around 5pm today and finished everything but "Six Meals a Day" around 10:30pm. With this in mind, I knew I only needed to play at 8am, 10am, Noon, and 4pm to unlock the achievement, so I simply adjusted the Time Zones and double checked it with the Time Format to make sure I had the time I needed.
I then loaded up The Maw, hit play game, loaded the level 'Planet Maw' for good measure, and as soon as the level loaded, I hit start then quit so the game would save. I then went to the Dash and just repeated the process back to back and unlocked my achievement just 10 minutes ago. This is a great time saving method, and I hope my little tidbit helps anyone in doing this in the future.
"I don't fail...I succeed at finding what doesn't work