Month, Week, 3-Day and views show a single day of the month as the header

[osteele]

The Month view today (April 24) has an “April 24, 2018” header. If I advance a month, it shows “May 24, 2018”. I'd expect “April, 2018” and “May, 2018”. Even if it shows “April 24, 2018” when I'm viewing April (because that's what day it is), it shouldn't show “May 24, 2018”.

The 3-Day also view has an “April 24, 2018” header. If I advance, it shows “April 27, 2018”. The headers should be “April 24–26, 2018”, “April 27–29, 2018”, and “April 30–May 2, 2018”.

Similarly for Week.