These releases are not mandatory, but it is strongly recommended the upgrades be performed to ensure the best service experience. All firmware, including release notes can be found attached to this alert.

While the new releases enhance performance for non-PTT operations on all three phone models, it addresses the following critical issues associated with PTT:

• Challenges: This is official notification of performance challenges observed for Iridium Extreme PTT phones loaded with Iridium Extreme PTT firmware release HP15003.  When in PTT operation, these phones may encounter a longer time to join talk groups and to be granted the floor in talking on these talk groups.  Additionally, these phones may see a decrease in battery life due to the increased power required to support this sub-optimal operation.
   
• Background: The HP15003 firmware release is the firmware provided with the initial phones at the launch of the Iridium PTT service in 2015.  Since that time there have been 3 additional firmware releases provided to address bugs and enhance performance of the service – HP17002 , HP17004 and HP19002.  The latest, HP21001, is the appropriate release for upgrade from HP15003 or any of the subsequent firmware releases.
   
• Action: It is imperative that Iridium Extreme PTT phones operating in the field with this firmware upgrade to the HP21001 release--the current release for the Iridium Extreme PTT phone. While the phones will not cease working, it is very important that phones with this five-year-old release be upgraded as soon as practicable.