Evo - you are correct, but P16 wanted the time they are published!
Their validity starts at 0000, 0600, 1200 and 1800. They generally seem to be published about 3 hours before the start of their validity, but I don't think there is an "official" time for them to be published.
You could try contacting the Met Office for a definitive answer, though?
FFF
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