Bailiffs may lawfully enter the premises during the hours of daylight (that is to say, 30 minutes after sunrise and 30 minutes before sunset, except on a Sunday, Christmas Day, or Good Friday) through either an open window or unlocked door and may remove property belonging to you which value would satisfy the debt.
Bear in mind that Bailiffs are Officers appointed by the Court and are Certificated to the Court, so they do have the powers vested under the prevailing law. They may call on the services of the police in order to gain entry into premises.
But they cannot legally remove property which does not belong to you. However, don't try to box clever because if the debt is not satisfied you might well end up in prison for non-payment.