tbh, I got the impression you weren't listening.
But forget about traffic.
Operation London Bridge / Unicorn was to go into effect when the Monarch died, not before. Imagine if she was hanging on a few days and the BBC re-arranged their schedules like they did. The plan was clearly already going on well before 15.10, just watching the BBC would have told you that. (as well as the HoC events)
The time of death on the Queens death certificate isn't really proof of anything much tbh because it will obviously have to fit in with the narrative we were told.
And the time she died isn't really that important either