Steps to reproduce:
Result: the first time you open stats after closing the app or switching sites, tapping on the bars in the chart does not change the data in the modules. If you use an arrow to change bars or if you change to a different time period (DWMY), then it starts working normally. (2m29s)
Tested with WP Internal 12.6.0.20190604 on iPhone 6S iOS 12.3.1
@jklausa believes this is related to #11873.
I re-tested with WP Internal 12.6.0.20190604 and develop d780002de0 (12.6 alpha) on iPhone 6S iOS 12.3.1 and found it is working much better except for the graphs for individual post views such as Stats > Insights > Latest Post Summary > View more. (21s)

Would you like me to file this as a separate issue?
@designsimply ah, yeah — that is a separate issue. If you could file it, I’d super appreciate it :)
Certainly! Filed at https://github.com/wordpress-mobile/WordPress-iOS/issues/11894.
I think @ScoutHarris pre-empted you with fixing this before you got around to filing this :P Should've gotten fixed in #11892 :)