Either they landed at the same airport, they both can teleport or the house can teleport.
Maybe she has a car that can drive at the speed of light and the mc hasn't boarded the plane yet because she went back in time to get away from her guards.
The assassins are the protectors of time who want to kill her to stabilise the timeline, they already got the car. They need to kill her because she designed the car. It's just so simple if you think about it.
When she first started the car she accidentally called the mc over from an alternate timeline. It all makes sense!