Your diary will most likely have rules set up that maximise your diary.
A common one is no 2s on a 4 top - meaning you will not short sell your 4 tops.
However, there are days when you might want to disable this rule (i.e. valentine's day, special events or day when all your 2 tops are booked).
How to disable a rule for a particular Day/Service
1) Go to the diary date you wish to disable
2) Click on the spanner icon located above the book button
3) Click on Rules Exceptions:
4) This opens up a window with all your rules:
This will disable the rule for this diary date only.