As of 27 April, the TAS system will remain down for the time being. ICANN will not reopen the TAS system until they are able to notify all applicants who were affected by the 11 April glitch. This is a consuming process.
“To do that, we are reviewing internal system logs and full packet-level capture of all traffic to and from the application system from 12 January through 12 April.”~ICANN
Once all affected applicants have been notified, it appears the TAS system will be scheduled to be reopened.