Are you talking about annual leave or a wallington week?
If you book a weeks annual leave containing a bank holiday, it should be credited back to you there and then. There should be a column on the right hand side of your leave sheet showing any bank holiday credits.
If you are talking about a wallington week, then a day in lieu will need to be credited manually by a manager, or you can of course take overtime for the bank holiday instead.
In either case, yes you are entitled to a day in lieu if your week off has a bank holiday in it.