Import Error: Timestamp format must be yyyy-mm-dd hh:mm:ss[.fffffffff]

Issue Summary

Error when importing Jira Server file into Cloud. Timestamp format must be yyyy-mm-dd hh:mm:ss[.fffffffff]

Steps to Reproduce

1. Export backup from Jira Server
2. Extract file and grep for CustomFieldValue string in entities.xml

   grep '<CustomFieldValue id=' entities.xml
   

3. XML file contain CustomField lines contain and update field which does not have the correct data format. Examples:

   <CustomFieldValue id="13196957" issue="813688" customfield="10082" updated="1589885159355" stringvalue="10210"/>
   <CustomFieldValue id="13196958" issue="813688" customfield="10021" updated="1589885159356" stringvalue="10019"/>
   ....
   

4. Problem is this line:

   updated="1589885159355"
   

Expected Results

• Jira Cloud to process the timestamp and convert it to the correct format. Previous fix on JRACLOUD-67557 allows import to proceed. Seems to be a regression

Actual Results

• Import fails with the following error:
  
• Related to previously fixed Server > Cloud import error: JRACLOUD-67557

Additional Notes

This can happen for other date time stamp values besides custom field value. Please contact Atlassian support if you need help with identifying the corrupt dates from your backup file.

Workaround

Currently there is no known workaround for this behavior. A workaround will be added here when available