Actually, the move of all the pseudobulbous Epi's with free lips to Encyclia was done many years ago. I'm not sure of the date, but I know it predates 1970. By this time, however, many hybrids had already been created and registered using the old name of Epidendrum atropurpureum...so the name has remained extant for horticultural purposes. Since the move to Encyclia, some of the Encyclias have been further split or re-lumped into new genera. Enc. citrina was moved to Cattleya briefly then into its own genus (Euchile, along with Eu. mariae). Encyclia cochleata was moved to Anacheilium then re-lumped into the newly proposed Prosthechea. Some other Enc's followed similar fates as well.
The RHS is actually making moves (now that the database is fully electronic) to correct some of these registration issues to reflect new taxonomy. I don't know how far down the line they plan to go, but I know that some hybrids have been reassigned to new pseudo-genera due to taxonomic changes.
Taxonomy is a constantly changing field, as it is very much a matter of opinion...what traits separate certain plants from others enough that they warrant their own classification? What traits make a plant similar enough to others that it should be included in that group? Opinions differ, and thus there is a lot of give-and-take, forcing us orchidists to either a) settle for one name and stick to it or b) read the latest taxonomical news like the Soap Opera Digest to find out what may or may not have happened to our favorite characters.