This link helps you plan your move to Oracle E-Business Suite Release 12.2, providing the following resources:
An in-depth Oracle E-Business Suite Technical Planning Guide that covers the numerous considerations involved in your move to Release 12.2
A navigational flowchart that shows you the high-level steps required for a Release 12.2 implementation
A checklist you can use to ensure you meet the essential prerequisites for a successful Release 12.2 go-live
The most current version of this document can be obtained in My Oracle Support Knowledge Document 1585857.1.