Unable to import requirements, search requirements, file defects, search defects on Jira Cloud
This was unrelated to the 6.6 release. Instead, it was due to GDPR changes being rolled out by Atlassian for all Jira Cloud customers starting on Feb 19, 2020. Even though Zephyr was updated earlier to comply with GDPR, it still used an outdated Jira library that failed with the latest updates.
Updated internal Jira library as recommended by Atlassian.