The Overwatch Summer Games 2020 end date is doubly mysterious, as Blizzard has yet to even reveal the start date. Here's what we can surmise based on when the event has gone live in the past, and how long it has lasted once available.
Overwatch Summer Games 2020 End Date
For most of Overwatch's history, the Summer Games event has started in early August. That includes the first three years of the game's existence: 2016, 2017 and 2018. Blizzard threw a curveball in 2019 when it moved the start date up to mid-July.
The developer never gave a reason for the change, which makes it difficult to predict whether or not it will stick to that new timeframe. It's hard to know if what made the change necessary or preferable will still be true this year, or if the developer will revert to the August release.
If Blizzard decides to revert to its old release pattern, the event will likely begin in the second week of August and run until the end of the month. If it keeps the new release frame, the event will begin roughly two weeks into July and wrap up in the first week of August.