Navtext content question

[extravert]

What does 'CANCEL THIS MESSAGE' followed by a time mean at the end of a Navtext message? For example this message (swiped from another post here)...

ZCZC PA94
NETHERLANDS COASTGUARD
NAVIGATIONALWARNING NR 94 210605UTC DEC
LOST FOUR WINDMILL BLADES
SIZE 21 X 1,5 METERS IN POSITION
52-37.1N 003-17.5E
CONSIDERED DANGEROUS FOR NAVIGATION
CANCEL THIS MESSAGE 211435UTC DEC
NNNN

has a time stamp of 9:06pm at the beginning, and then the 'cancel this message' at the end followed by another time stamp with a value 8 minutes later. Have they changed their minds in the intervening 8 minutes?

<hr width=100% size=1>One day, I hope to own a real boat.

 

[Roberto]

Maybe because it takes 8min to a windmill blade to sink ?

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[Ric]

First, you're misreading the timestamp. The first two figures (21 in this case) refer to the date. The next four are the UTC. So as you can see, there is a lot more than eight mins before the cancellation.

The cancellation time signifies the end of validity of the message. So in this case, it means that the hazard will no longer be there after the specified time. If it is still there, another message will be issued before the cancellation time.

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[extravert]

That makes more sense. Now I know. Thank you.

<hr width=100% size=1>One day, I hope to own a real boat.

 

[Gunfleet]

If they don't know where it is how do they know it won't be there?

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