Depending on how that goes, they will decide upon dates and times for similar tests in North America and Asia.
The Unity article says that the studio is first launching a test from 4 PM to midnight British Standard Time on Thursday, August 20, and at the same time on Friday, August 21.
No dates have been announced for these future tests, with Capcom holding back on confirmation until the results of the first regional tests are completed. Capcom’s announced that it intends to run a series of region specific server stress tests today and tomorrow, and you’ll need to be ready to fight from 16:00PM BST on both days to participate. The stress tests are just the beginning and once those tests have been passed, a “global beta test will still take place for the previously promised five-day stretch”.
It should be noted that your Street Fighter V beta will still work, and you should not require another code, however please ensure you have installed the latest patch, if your beta has not automatically updated. Capcom sold beta access as a pre-order bonus for Street Fighter 5 in North America, so beyond collecting play data, it is pretty important that it makes good on the offer.