Kathmandu is 2.75 hours ahead of Riyadh
Best overlap: 8:00 AM to 4:00 PM in Riyadh is 10:45 AM to 6:45 PM in Kathmandu.
The overlap falls at 8:00 AM to 4:00 PM in Riyadh, or 10:45 AM to 6:45 PM if you're in Kathmandu. Scheduling is forgiving here: with 8 hours of overlap, a missed slot just means picking another one the same day.