Selected answers from the Dumb SEO Questions G+ community.
Perry Bernard: It was already connected using the verification you used for the http version. Typically, it takes 3 or 4 days for data to start coming through, and will appear like a "new" site while their index adjusts between http and https (so long as you have redirects in place).
Dean Hua: I had accidentally deleted the http version. Oops :(
Perry Bernard: no big deal. Just re-verify and you get it all back
Perry Bernard: from today Google started grouping properties in GSC automatically too so you can now verify your domain once at DNS level and then google will automatically assign all properties into one group eg. https, http, www, and even m.
Ata Ur Rehman: I must say that it takes a minimum of 2 days and maximum of up to 5 days.