The announcement about GPS week rollover is also posted in our NAVAREA III:
NAVAREA III preview 0305/2019
MEDITERRANEAN AND BLACK SEAS
POTENTIAL PROBLEMS FOR USERS OF GPS RECEIVERS.
1. USERS OF GPS RECEIVERS ARE ADVISED OF POTENTIAL PROBLEMS DUE TO GPS WEEK COUNTER ROLL OVER ON 06 APR 19.
2. THE GPS SYSTEM TRANSMITS TIME TO GPS RECEIVERS USING A FORMAT OF TIME AND WEEKS AFTER THE START DATE OF 06 JAN 80. THE DATA FIELD IN THE NAVIGATIONAL
MESSAGE SENT BY GPS SATELLITES CONTAINING THE NUMBER OF WEEKS AFTER THE START DATE IS LIMITED TO A MAXIMUM OF 1023 WEEKS. WHEN THE GPS SYSTEM REACHES WEEK 1024,
THE SYSTEM WILL REVERT BACK TO WEEK ZERO.
3. SOME GPS RECEIVERS ARE KNOWN TO BE UNABLE TO MAKE THE TRANSITION FROM WEEK 1023 TO 1024. IF THE GPS RECEIVER IS OUTDATED OR LACKS PROPER UPDATES,
THE RECEIVER WILL REVERT TO READING THE WEEK ZERO AS AUGUST 1999. DURING THIS TIME THE INTERNAL CLOCKS OF THESE GPS RECEIVERS WILL EXPERIENCE A LACK OF ABSOLUTE
REFERENCE AND MAY GIVE THE WRONG TIME AND POSITION OR MAY LOCK UP PERMANENTLY.
4. SOME OF THESE GPS RECEIVERS ARE REPAIRABLE WITH UPGRADES AND OTHERS WILL BECOME UNUSABLE. USERS ARE ADVISED TO CHECK WITH THEIR GPS MANUFACTURER REGARDING THE STATUS OF THEIR RECEIVER.
5. FOR FURTHER INFORMATION SEE:
A.
WWW.GPS.GOV/CGSIC/MEETINGS/2017/POWERS.PDF .
B.
WWW.GPS.GOV/GOVERNANCE/ADVISORY/MEETINGS SELECT NOVEMBER 2017 AND THEN TIMING CRITICALITY NOTE ON GPS WEEK-ROLL-OVER
C.
WWW.GPS.GOV/TECHNICAL/ICWG/IS-GPS-200J.PDF.
6. FAILURE TO VERIFY YOUR GPS RECEIVER COULD LEAD TO SERIOUS NAVIGATIONAL PROBLEMS PLACING LIVES AND PROPERTY AT RISK.