As per the latest United Kingdom AIP, it is now mandatory to modify the last assigned transponder code to 2000 in the Shanwick FIR within 10 minutes instead of 30 minutes. This change will make the timing consistent with the requirements when operating on Tango 9, Tango 290, and Tango 213. The 10-minute requirement is also in place when entering the Shanwick FIR when transferred from Reykjavik and no later than 10 minutes after entry. This procedure does not affect the use of Special Purpose Codes 7500, 7600, and 7700 in cases of unlawful interference, radio failure, or emergency.

According to a communication from NAV CANADA, Gander Oceanic has decided not to implement the change to a 10-minute requirement at this time. The 30-minute requirement will continue to be in place. Be sure to refer to the current AIPs where operations are planned and the current version of NAT DOC 007.