you're updated! glad to see some movements for you as well.
Don't do anything for the medicals just yet. There are several scenarios.... if London can issue your PR before that, nothing will be needed. If they can issue it, but it's quite close to the expiry, they will contact you and ask you if you're able to land before the medicals expire, and give you the option - either get an extension, or land by the date. If you're in Canada, that's quite feasible, if not, that might be quite difficult... If they are not ready yet, but getting close, they will extend your medicals automatically (and you won't know about it until your PR is issued..)... the last option is that they ask you to re-do the medicals, but that's in case you have done the medicals more than 15 months ago, and there are other things preventing them from issuing the visa (background checks, etc). So - there are lots of options, and best is... to wait and see, as usual!
hopefully you'll hear from them soon, or just see DM on ecas, and be done with it!
Good luck,
Sweden