Guys heads up. Looks like someone just got an in-person test.
Look at
this post. There is no test window and the words "online test" is not seen on their status update. They've given the applicant a single date (June 7) to attend the test. The OP still hasn't received an email.
We're still NOT SURE if this is an in-person test but be sure to check that thread when the OP responds once s/he receives the test invitation in the email.
UPDATE: This could just be IRCC modifying the process to allow only 1 day for online tests instead of the 21 day window. We won't know until the OP gets back to us once s/he received an email invite.