In my brokerage, each agent inputs their own listing and it must be done within 48 hours of obtaining a listing, unless the seller chooses to withhold it for some reason. Sometimes it is withheld for a time in order for the seller to make some improvements, or for staging, photographs or virtual tours. If you are looking at secondary sites such as Realtor.com, Zillow or Trulia, listings may not be posted in real time and some listing status data may not be up to date because of how it is fed into secondary systems. Some brokerages do not allow their listings to be fed into secondary sources, only into the MLS. Ask your agent/brokerage for a copy of the MLS printout.