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For more details on Data Center compatibility, see S/Notify for Data Center.
How does this affect youexisting customers of S/Notify for Confluence?
Data Center Customers
Customers of Confluence Data Center must convert S/Notify to the Data Center edition if they update to version 3.4.1 or later. Atlassian will refund out any unused portion of the server app license for the purchase of a Data Center app license. Within the first 30 days of the purchase, you can receive a full refund. After 30 days of purchase, you will receive a pro-rated refund based on the date from when you request the refund.
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