The April 12, 2016 release of the RDA Toolkit included a few revisions to MLA's Best Practices and the supplements.
BP 220.127.116.11 now includes a recommendation to record the type of corporate body in all cases, whether or not the term is used as a qualifier in the authorized access point. Generally the LCSH term “Musical groups” for performing ensembles is used (note the use of the plural for “groups”) and the term’s source is recorded in subfield 2.
BP 18.104.22.168 now includes guidance for cases of doubt as to whether the preferred name for a performing group conveys the idea of a corporate body. In such cases, an addition for the type of corporate body is made as instructed at RDA 22.214.171.124 (and also RDA 126.96.36.199). A qualifier such as “Musical group” in not added simply to bring out the musical aspect of the corporate body.
Supplement 1 now includes values for audio cartridge (e.g., 8-track) in the chart. Supplement 1 has also been revised to clarify the non-RDA terms to which “without $2 rda” applies.
The Best Practices are accessible only via the RDA Toolkit. The supplements are accessible via the MLA CMC website.
Thanks to all who were involved in this effort.