Hi, I just stumbled across shocking news. I don't know is it easter egg or real but since it's from 28th march it could be real. Anyway even if it isn't truth it has interesting plot, related to vault climate 
Original article is written in polish so i'll translate script of it - i'll try my best
Link to original version: http://www.pojezierze.com.pl/content.php?cms_id=841

Original article is written in polish so i'll translate script of it - i'll try my best

During 80s some soldier made small workshop in barracks cellar. One thing was strange - when there was energy shortage in whole city he always had power from electric installation. There were simply two cables coming from wall.
Few weeks ago foreigner was nicked for exchanging false dollars. Later police found out that money was genuine but had been simple pulled out from circulation years ago. Foreigner didn't have any id so he was released and followed. He literally disappered after entering one of a houses. Investigation team found hidden entrance to tunnels.
What police found exceeded everyone expectations - tunnels was so wide that car could be fit, they were tenths kilometers length and some people were found there. Totally 67 people (including 12 childs) were found - they hadn't any ID.
In progress of enquiry some shocking facts were revealed. These people lived there from 40s, originally bunker was designed as shelter for SS officers and selected womans that will wait for reborn of nazism, for long time after war they were supplied by agents from 'outside'. They were living there for 3 generations. Caught person left shelter in search for medical supplies and because he didn't had polish currency he tried to exchange dollars.
Link to original version: http://www.pojezierze.com.pl/content.php?cms_id=841