Why would the Union tell me to limit posting on BlackBoard? Wouldn’t this negatively affect my students’ learning?

The Bargaining Team’s directive is to refrain from posting your learning materials directly onto BlackBoard. This is not to say that you shouldn’t provide all necessary information to students. You should still post the “minimum required materials” onto BB at the start of the semester, which includes the course outline, your critical path, and a welcome note. At no time will a work-to-rule mean that we don’t provide students with their learning materials, but it would be a good idea to distribute your course materials to students through a different platform, such as DropBox or Google Drive (preferably with password-protection), and to make recordings available to your students via YouTube, Loom, Vidyard, or, Google Drive (again, password-protection is recommended). We believe that these measures would maximize the effectiveness of our current work action (and therefore minimize the need for further escalation), and maximize faculty ownership over their own work product.

Here is some information on alternatives to BlackBoard and MS Teams: Alternatives to BB and MS Teams