Excerpt from Day 1 Cross-Border Plan for 5 Cities and 4 Countries

Day -7

Internal Comm: FAQs (IT, Payroll info: semi-monthly to bi-weekly, Cobra, Remote I-9s (notarized), holiday, FICA withholding, insurance deductible)
Full List of Employees (preferred name, email address, cost center, job title)
Email Groups
Establish new vendor as supplier (interim IT support)

Day -3

Internal Comm: TBD

Day -2

Internal Comm: TBD  

Day -1

Internal Comm: TBD
Acquirer email addresses created for all Acquired Co. employees
Update User Access Matrix to IT PMO (facilitates Acquirer system access)
Cancellation of Benefits
Cancellation of TransAmerica 401(k) Plan
Obtain Administrative Access (GoDaddy.com, gmail tenant)
Internal Comm: FAQS (IT Access Instructions, usernames and temp passwords)
External Comms: Press Release (Markets are open on 10/8)

Day 1 

File 8K
Bank Account Control
Payroll cutover; HRIS
Employee complete Consent for Withholding
Employee sign Employee Handbook 
HR Presence On Site
Employee Sign Confidentiality Agreement (DocuSign)
Employee Sign Contract / Employment Offer (DocuSign) ...