THis is just a rule of thumb.
You can take it at any time you can take with food or without. For best GH boost take as far from a meal as possible.
My training partner has been taking 1 at 3pm and 1 before bed and he is looking nasty. Calorie deficit, just getting drier and harder every day.
One of the guys at the shop is taking in calorie surplus and is just taking whenever he can get it in, trying to take away from meals and hes steadily growing.
This stuff is super versatile.
Good on a cut/ deficit
Good on a growth phase / surplus.
Dont over think it
You will be happy with the results either way is my guess.