|Can you answer that?|
You can do this without hiring more staff. Train, promote and empower your front desk night shift and put them to work in social media and marketing. In fact, you should have your best and brightest staff on the night shift, the ones who can give the right answer and make the right decision without referring to a manager. These are your future managers proving their abilities. Set up a system to insure that there is always someone on social media duty throughout the day, night and weekend. At one hotel, the staff has a small koala bear with a clip which is clipped to the screen of whoever handles social media now. When that employee goes off duty, the little bear must be moved and clipped to someone else's screen, so it moves around the back office, the front desk, even the GM's desk through the week and there is never any gap of coverage.