Read More links leading to 404, then to a Page

Hi, All links to an individual posts are not working, including the "Continue Reading" link and the link from the article title on the home page. I changed the default Permalink Setting - I know that shouldn't cause a problem, but perhaps it has. Yesterday evening the links were all leading to a 404 page. Today they're leading to a Page (not to the Post). In the future, I'd like to use different default Permalinks (i.e., 2014/Winter/ now, then 2014/Spring, 2014/Summer, etc.). Is this possible? My site is http://www.activewomantraveler.net. Is there a solution for this? Thanks! Annie Tobey