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So I'm planning to send a letter to the Jonas Brothers when they're at the Qwest Center on the 23rd October. Living in the UK a letter by Airmail to America takes 3-5 days as stated on the Royal Mail website, following the day of posting. After I've gave it to the post office ready to send to the US how long does it then take from the US post office to sort out the mail to where it's going? Like is that an extra 3-5 days on top of that or a day or something? Can anyone give me an ideal date for when to send the letter?

To be totally safe, send it 10 days beforehand. I think it takes 2 days max. to sort the mail out.

Thank you