The BSc vs. Phd thing has to do with being overqualified for the job being offered. Phd's are already quite specialized in their field while BSc's only have the basic knowledge to build on. The Phd going for a BSc job is likely asking for more money or if not, maybe he just wants it for short term while he looks for something better. The BSc is more easily moldable. I have heard of employers who prefer to hire people with less training because they are happy with how the workplace is being run and don't feel they need outside ideas, instead they can train their people to work with their methods. The Phd's are good for other jobs where they need their specialized training that a BSc doesn't have.
As for the IELTS. If they ask for general IELTS, they probably have a reason but if you have an academic already, you can ask the embassy or CIC if the academic would be accepted. If somebody decides to check this out, please report back here so we'll all know.