Just had a look on Wembley stadium website and it states that there is a 10:30pm curfew for Wed, Thurs and Sat concerts and 10pm for Sunday.
https://help.wembleystadium.com/support/solutions/articles/9000029218-i-need-to-catch-a-train-after-the-coldplay-concert-what-time-does-it-end-
Guess that this will mean Coldplay will be on around 8:30pm latest. Hope this doesn't mean that the start is visually less stunning than we have seen for recent Latin America gigs, seeing as it will be still be light at that time in June