Issue

Due to the size and complexity of the organization, the migration must be executed in manageable "waves," with each wave containing no more than 5,000 users.

A key challenge is ensuring business continuity and minimizing disruption, while also accommodating specific group preferences and technical constraints.

Background & Context

• Wave Structure: The migration is divided into four personal data waves (1-4) and one wave of shared data (5).
• Stakeholder Involvement: The proposal was validated in the Business Steerco on February 17th, with input from business representatives and leadership teams.
• Special Considerations: SyWay, although classified under IT, has opted out of the first wave. This required careful adjustment to the headcount and migration schedule.
• Composite materials: Identified as critical operation, requires dedicated treatment during the migration.

Wave preparation process

Assumptions

• At the beginning:
• IT (already heavily involved in pilots + typical first wave population & able to support their peers)
• TBC: one Composite site of 80 pax as part of the first or second wave? (suggestion from the business representative)
• To be discussed: hybrid approach with sites populated by many different functions: Silex to link with IT, Aubervilliers to link to Novecare & Aroma, Explorer TBC
• In the middle:
• Specialty Polymers (filling one full wave because of its size)
• At the end:
• GBS (GBS is proactive on the migration topics but their heavy use of shared resources might prevent them from migrating sooner)
• Composite materials (they have the most specificities)
• TBC: Oil&Gas (to leave time for data identification as part of Titus)

Constraints

• Approx people per wave = 4000 (not more than 5000)
• Data volume = 2 weeks of pre-staging per wave minimum (i.e. historical data pre-migration) 
• First Wave preferably smaller (either in amount of user/data, and/or in complexity)
• Ex: users with special characters in the documents names or email titles typically generate more migration errors
• Shared resources wave:
• Watchpoint on integrated mailboxes that have to be reconfigured during the cutover weekend
• Shared drives renaming will be frozen from beg. of April until their migration mid June
• Specific to Organizations:
• GBS & related functions = not at the end of a month (closing)
• Requirement from GBS LT: Finance, HR & Procurement BSA's should be in the GBS Wave

Impacts

• Mixed use of GWS and M365 across organization.
• Potential collaboration and communication challenges.
• Increased IT support demand.
• Need for clear communication and user guidance.
• Duration: ~4 weeks until shared data is migrated.

Options considered

Option 1: 

Option 2:

Option 3:

See also

The following section describes relevant documentation: