Shared air tag showing different locations on different find my apps

Today i have been travelling, and i have one air tag in my hold luggage, and one in my hand luggage. Both are shared tags, so both myself and my partner can use them.

It was working fine, and I could see the location of both tags until the third leg of my trip, when my hold luggage didn't make the plane, and was showing in city 2, and when i landed in city 3, for a while i could see it updating and moving around the terminal at city 2 airport.

I am now in city 3, and the tag has stopped updating for me. I still see it on my phone as in city 2, with no updates for the last 12 hours.

However, my partner (in city 0, about 1500km away) sees the same shared tag as now being in city 3, and has updates from a few minutes ago. My iPad, using the same apple id as my iPhone shows the location of the tag as being in city 1,which was the last time it was used in the vicinity of the tag.

How is it that the shared tag is working for one person all of sudden and not the other, and that the same apple id, on the same network, can show the same tag in two different locations?