San Diego is 13 hours behind Islamabad
There is no standard 8-to-6 overlap. Someone joins early or late.
Islamabad and San Diego are 13 hours apart, and that gap is wide enough that their normal 9-to-5 workdays never quite touch. If you meet regularly, fix one off-hours slot and rotate it between Islamabad and San Diego so the burden doesn't fall on one team. These times hold for most of the year, but San Diego's daylight saving (which Islamabad doesn't use) shifts them by an hour twice annually.