Payments won't show up neccessarily until the end of day they are journalled to the merchant account. The transaction can be authorised and appear later in certain circumstances depending on the merchant arrangements.

For a Monday delivery, assuming Saturday dispatch, you wouldn't neccessarily see the charge on the account until end of play on Monday as the weekend isn't a banking day so transactions sometimes queue.

Personally I would guess that a Monday pickup is more likely than a Saturday one though.