Everybody knows the story by now; when Capcom first started the beta tests for Street Fighter V, their servers where overwhelmed with the sheer number of players trying to get in, keeping fans from being able to play and forcing the developers to reschedule.
To make sure that the same issues don’t crop up when the beta does come back, Capcom has announced that they will be conducting regional stress tests to gather information. The first of these will be for Europe, scheduled for Thursday, August 20 between the hours of 4 PM and 12 AM BST, and again on Friday, August 21 during the same time period.
Once Capcom has enough data from Europe and is confident with the results, North America and Asia will be able to get in on the action during their own stress tests. The official global beta will follow sometime afterwards.
Take note that these stress tests will not count against the rescheduled beta; rather, Capcom states that these five days are an added bonus.
Source: Capcom-Unity