lobby is separate from the window-service lobby, so that the former may be kept open for longer hours or around the clock, while the latter is locked after business hours. In the U.S. since the 1980s, in cities and large urban areas, post offices have tended to close box lobbies overnight because of the tendency of homeless people to use them for sleeping quarters. As a result, some box lobbies are accessible after hours by customers who are provided a code to a door keypad. In addition, some post offices are located in rented facilities such as shopping malls. As a result, PO boxes can only be accessed while that facility is open. Packages If a parcel does not fit in a PO box, the postmaster will leave a note advising that customer to pick up that parcel from the counter. In some post offices, a key will be left in the PO box that corresponds to a larger, locked box (parcel locker) where the patron may pick up their package if a signature is not required. Most often, in this case, once the key is used to open the larger, locked box, the key cannot be removed again by the patron, but the door cannot be secured either. Notes will also be left in the PO box in respect of cash on delivery (COD) and registered mail that has to be signed for. In 2011, the United States Postal Service began a pilot program with a computerized parcel locker kiosk system, called "gopost" which installed larger boxes to handle package pickup from an unstaffed station. A given box can be used by multiple customers thanks to the integration of a computer which accepts a delivery code. Package delivery by private carriers Until 2012, package delivery to USPS post office boxes was not available from private carriers like UPS, FedEx and others. In early 2012, the Postal Service introduced a P.O. Box Street Address (PBSA) service that allows box-holders to combine the street address of the post office where their box is located with their post office box number into a street address format. A mailing industry publication called the new service "a great service for people who already have a PO Box and don't want their packages delivered to their home." Locked bags and caller service Users receiving very large quantities of mail can use "locked bags", which are