Issued 19 December by Eurocopter :
The second ASB (EC135-28A-019) introduces a revision of the flight manual with regards to the low fuel warning and the fuel pump caution indications. The corresponding airworthiness directive to be issued by EASA will be an Emergency Airworthiness Directive, meaning the revision to the manual must be made immediately. This is not because there is a safety concern. Rather, the emergency directive ensures the revision is made immediately instead of at the next scheduled update of the manual.
Issued 23 December by Eurocopter :
Following the Alert Service Bulletin released on December 19, one-time checks on the fuel tank system of the worldwide EC135 fleet continue. As of today, 264 sensors have been tested. Of these, 12 needed to be cleaned but were fully functional afterwards, while two failed and needed to be replaced.
Eurocopter continues to monitor the checks closely and will provide updates as more information becomes available.