I haven't checked the source but the way I see it is if your exams were due to "expire" validity wise between March 2020 and May 2021 you get the extension. I would assume because of the various Covid lock downs.
If your exams are going to expire in Feb 2023, I'd crack on with the flying. I wouldn't wait another second for the CAA's response.
No idea re your 2nd question.