We all get these, all the time and not only from eBay.
It's a newish security system to alert users when an unexpected login appears to have been made - which in my experience can even mean logging in at an unaccustomed time of day or night.
The daft thing is that the location given is unrelated to the user's location, and seems to be the location of a main remote server. You would think they would explain this.
You can probably find more info. online, but my policy is to dismiss these warnings provided I did actually log in around the time stated.