As has been said we’d need to see the raw stats for BA but I’ve not heard anything via the various “rumour controls”
that would indicate there has been an unusual increase in the amount of medical diversions. I think they are as random an event as always..which by it’s nature means sometimes there will be “clumping” of incidents.
Of course as a general point with the ever increasing use of social media and the press monitoring the same, and the various flight tracking sites there’s more chance of events coming to public attention.