This page outlines the steps to migrate to the New Connector if you missed the migration window. As Atlassian has removed the P2 Connector from JIRA Cloud, some extra steps are required in order to migrate the P2 Connector data to the New Connector.
At the end of the steps, you will have:
Created a site backup of your JIRA Cloud instance.
Set up a temporary local JIRA Server instance and restored the site backup to the instance.
Produced an export file of the P2 connector and imported it into your JIRA Cloud instance.
These steps may take a few hours to complete.
In JIRA Cloud, produce a site backup:
Visit System > Import and Export > Backup Manager.
Ensure Backup additional files (including attachments, avatars and logos) is unticked.
Click on Create Backup for Server.
Download the JIRA backup file. When prompted to authenticate, enter your JIRA Cloud credentials.
Download the latest JIRA Server binary matching the applications you have in JIRA Cloud (e.g. JIRA Core, JIRA Software, JIRA Service Desk) from Atlassian's download page.