Find my friends - location

I've done all the steps to try to resolve this issue. It seems to be just a certain location that I'm having this problem. Its about 2 miles off...

My quesetion is this:

When I first open the location tracker and it shows the marker at location X (2 miles away), but then quickly changes to location Y (where its supposed to be) is it because they were at location X recently or is there a problem with the GPS?