Congrats on your MR.
Please don't bother yourself about any further update, just go for your medicals and expect your PPR. I also got the same mail for my MR in June without any further update and i was also bothered but I went ahead to do the medicals at abuja clinics and the result was upload exactly 7 days after the medicals. I saw medical received on my ECAS 4days later and got PPR after about a month of the update. I did not even send my evidence of medical done to them and they never asked for it. I don't even know till date who the visa officer who handled my case is, I only know the one who sent my PPR.
Just relax and do the needful for now.
I will send you a PM now as regards registering for COA in Abuja which is coming up on Tuesday 15 of September (next week Tuesday).