Islamabad is 13 hours ahead of Portland
There is no standard 8-to-6 overlap. Someone joins early or late.
Portland and Islamabad have no natural overlap. The 13-hour gap is simply too large for regular working hours to meet. Treat the handoff like a relay — Portland wraps up and leaves notes for Islamabad to pick up as their day begins. A quick caveat — Portland's clocks move for daylight saving and Islamabad's don't, so the times here are right for only part of the year.