To make sure that the migration process to Office 365 runs smoothly for all BPOS (Business Productivity Online Suite) customers, Microsoft is taking a conservative approach and piloting the move with a hand-selected set of customers.

If all goes well, the company plans to begin "broad transitions" to Office 365 for BPOS customers at some point in September, the company said in a statement e-mailed to IDG News Service.

Even then, Microsoft will make an evaluation for each BPOS customer's transition timing based on their and other technical criteria, the company said.

"Our goal is to provide our existing customers the best experience when transitioning to Office 365. The one-time transition process is an important step to rolling out the service and we're focused on getting it right," the statement reads. "We have customers who span different needs and environments and through these early pilot efforts, we're able to improve our services and support to ensure that our current customers get the best possible experience they expect from Microsoft."

New customers and those who want to migrate their accounts and data from other non-Microsoft suites can sign up for Office 365 today.