Trending @Accenture; When employee is tagged to a project but not assigned work, does probation period ends automatically or gets extended by workday manager?

When an employee is tagged to a project/client but not assigned work - does default probation period of 6 months end automatically or it get extended by manager shown on workday? If it gets extended , after how much time it will end? Is it required to speak with manager shown on workday before default probation end date?