It's timeless advice.

Etiquette expert William Hanson has revealed whether you should arrive early, on time or 'fashionably late' to a dinner party.

And it's bad news for early birds.

William dispenses his advice in his new book Help I Sexted My Boss – A Hilarious Guide To Avoiding Life's Awkward Moments, co-authored by Jordan North.

In the conversational tome, the pair answer the question 'what time should I arrive at a dinner party?', with Jordan admitting that the issue causes him a lot of stress.

He writes: 'If someone says "come for 7pm", what does that actually mean? Do you turn up on the dot? Or do you show your face fashionably late?'

William replies: 'If I say "come for 7pm", I don't mean turn up at 7pm. I would expect you to arrive by 7.10pm, maybe 7.15pm. But no later.'

However, Jordan complains that this is 'weird etiquette gaslighting'.

'Just tell me what time you want me to be there and I'll be there,' he says. 'I agree that you should never be early, because that's just annoying and people are flapping about getting things ready. But if you're told to be there for 7pm, the host should be ready for 7pm.'

William responds by explaining that 'the ten-minute-late rule was something that older generations lived by', and concedes that nowadays, however, 'people's time is so precious, this is changing'.

He adds: 'Although I may not like it, I do think Jordan is probably right there. I also agree that guests should never arrive too early. I'd rather you were an hour late than five minutes early.'

William also reveals the true meaning of '7 for 7.30', explaining that it means 'any time from seven but not after 7.30… as that's when we will start eating'.

The optimal time, he suggests, is 7.15.

Help! I Sexted My Boss by William Hanson and Jordan North is out now (£20/CAN $42.95), published by Penguin Random House. For more from Mr Hanson visit his TikTok and Instagram profiles.