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Max 10 subtasks
When you migrate Scheduled Issue with more than 10 subtasks, only 10 will be migrated. 10 subtasks is the app limit.
Note: On request, we can increase your subtasks limit, but it won’t affect migration process limitation. In that case, the limitation during migration process will be the same as on the Jira Cloud instance.
Recommendations
Clean up
Remove not used templates, if you are keeping old templates just to have access to that template execution history - it won’t be migrated. That’s why it is better to build some Jira filter or add some new/special label to mark those issuesClean up, again
Migration is a great opportunity to make some adjustments and removal of not used templates. Again remove unnecessary and not used templates.
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