Season 2, Episode 10 is the most recent one. Next episode is aired July 21st (or July 22nd if you are in the future like me).
Brief descriptions of eps do contain spoilers on that page.
As to it being a continuum and all the other theories I have no expectation of ever finding out. So far it's avoided the whole conspiracy upon conspiracy spiral but it may well end up that way. I would love it if it had a satisfactory conclusion, especially if we think we are getting the real info and in the final episode we are proved wrong and it ends with a debatable mystery. But really I'm happy as long as it doesn't end up chasing it's own tails like Lost which shitted me to tears.