There's already Liturgical year, which discusses the Proper of the Season, although it can be a bit confusing since it discusses Catholic and Protestant uses, which aren't always the same. Any article would have to include both the pre- and post-Vatican II calendars, most notably Septuagesima and Passiontide as well as Ordinary Time vs. Time after Epiphany/Pentecost. The only change I see would be to create a specific "Roman Catholic Liturgical Year" article. As for the 1962 Calendar of the Saints, I created the older one mainly because I already had the pre-1955 calendar in electronic format, it's more consistent with past use since Trent, and it includes feasts that were later dropped. I think the same article can be used for both the 1955 and 1962 calendars, adding the rank of feasts (Double/III Class), and some sort of special formatting or asterisks for Feasts which are only on one or the other.  
Re-reading the first comment, I'm also starting to like the idea. We can have one article on the year in general, what effect it has on the liturgy, and the arrangement of the liturgical books, with sections or sub-articles on the Proper of the Season and the Proper of the Saints, both articles discussing the 1955/1962 and 1970 versions.