Routine A days are the days when most things are within your control. Routine B days have unpredictability built in: your sister's birthday, New Year's Eve, Father's Day, Mother's Day, Labor Day, 4th of July BBQ, Memorial Day, going on vacation, having people over, company happy hours and holiday parties, and the list goes on.
While most people tend to think each one of these are unique events, turns out that for most people Routine B takes over at least 2 days every week.
We have different habits on Routine A than on Routine B. Routine B is generally harder for weight loss which is why many prefer to put in more calories for those days. How you'll divide the calories each week is ultimately up to you but right now it's important to know that if you go 150 cal over one day, that's OK - ultimately it's the total WEEKLY calories that matter.
As long as you stay within your total WEEKLY calories then you'll lose weight at the expected pace! It doesn't matter if there's variation from day to day. If you were to divide those calories equally, then your daily calories to aim for would be equal your weekly ones divided by 7. Makes sense?
In the Fitness Reloaded program we'll talk more about how to become not just a Routine A, but also a Routine B pro. Because unless you master BOTH then you'll not be able to lose all the weight. Instead, you'll be worried about your social invites, you'll be suffering trying to restrict yourself from eating, then eating and feeling guilty about it, etc.