Did you ever go to elementary school? If you did, you would be able to add 7 to 9 properly, and whould get the correct answer, which is 16, not 15. Your exit permit expires on 16th of July. Besides, you always can see the expiry date on the exit permit copy. Moreover, even if your EP expired on July 15, as you wrongly calculated, it still would be valid till midnight, not till 6pm or 9 pm or whatever.
Did you ever go to elementary school? If you did, you would be able to add 7 to 9 properly, and whould get the correct answer, which is 16, not 15. Your exit permit expires on 16th of July. Besides, you always can see the expiry date on the exit permit copy. Moreover, even if your EP expired on July 15, as you wrongly calculated, it still would be valid till midnight, not till 6pm or 9 pm or whatever.