It might not be valid abroad but if Harry clampers gets you it works just fine in any country ( the alternative being to ignore all of the instrument messages and crash). You just cant rely on it for nav when abroad. But why would you want to go abroad when we have such lovely imc weather here. Also I've used it lots when it's technically vmc but in effect imc ( crossing the channel on a really hazy day)
The jfdi message is the one you have to take. You won't regret it.