My offer letter says they're offering me employment "no later than july 5". In e-mail communications however, they say they expect me to start July 10. I'm going to apply at the border July 8. Will this be a problem that the date says effective July 5, as this is before the date I go apply? Will the border guard have a problem with this and deny me based solely on the printed start date, or would I be able to explain that I'm planning to start July 10 as I was awaiting visa approval. Would they accept this or should I get another offer letter stating a different date?