Please find below the information from our Partner: Inmarsat
On 30th June 2015 another leap second will be added to the GPS system. A leap second is a one-second adjustment that is occasionally applied to Coordinated Universal Time (UTC) in order to keep its time of day close to the mean solar time. This change will have operational implications for all the IsatPhone Pro units running firmware version older than 5.3.0.
The firmware update can be found here: http://support.roadpost.com/kb/articles/361-isatphone-pro-firmware-version-5-8-0
This change will not impact users of IsatPhone 2 units.
Reason for notice: Planned maintenance due leap second addition
Services affected: GSPS
Regions/Spots affected: All Ocean Regions
Start of Maintenance period: 30th June 2015 21.00 UTC
End of Maintenance period: 30th June 2015 00.00 UTC
Terminal Types affected: IsatPhone Pro
Actions needed by user: if the current IsatPhone Pro is using a lower version than 5.3.0 the customer has to upgrade to the latest version.
We apologize for any inconvenience.