Factual error: The 15 bus in London does not go over Westminster Bridge.
Factual error: The winter car chase in Austria shows the Range Rover's license plate "IL 25768H", which stands for "Innsbruck Land" in the province of Tyrol, but the flag in the middle of the plate belongs to the province of Vienna. It should show the Tyrolean eagle. In addition, it contains too many characters.
Factual error: M drives a 2006 Jaguar XJ, which is rammed sideways into a concrete wall by a black pickup truck. Such impacts would fire both thorax and curtain airbags on both sides of the car; these would be visible in the wreck afterwards, as limp sheets of cloth dangling down the sides of the seats and door, respectively, but they aren't there. Without such protection, M and Bond would be severely concussed, and unable to function.
Factual error: When Bond's plane crashes head on into the Range Rover Sport, Hinx smashes through the windscreen, which shatters into small granules of glass, and lands on the bonnet. This would be quite realistic in the 1960's, but modern cars have laminated windscreens, seat belts, and large passenger airbags. Even if he undid his seat belt to shoot at Bond, or didn't wear it in the first place, the other two safety features would have kept him inside the vehicle. Not quite so dramatic, of course.
Factual error: The Aston Martin DB10 does not show a front licence plate, but it is required by law to show one at the front and back of the car in England and Europe.
Factual error: When M asks Q for Bond's location - and is told he's in Chelsea - the film gives a lat/long that professes to be Austria but is actually in the middle of the ocean. (00:52:40)
Factual error: The Number 15 London bus seen on Westminster Bridge at the end of the movie could not be there. The 15 runs from Trafalgar Square to Tower Hill.
Factual error: When Q tells M that Bond is in Chelsea the screen shows "Austria." The names of the roads are stupid. One name is SEEKLAUSSTRßAE. If a road like this exists it should read SEEKLAUSSTRAßE or SEEKLAUSSTRASSE as the "ß" in capital letters is written as "SS" (at least in 2015). An other one is MÖSERNßTRASE instead of MÖSERNSTRAßE. Fun fact: Möse is a vulgar German word for a specific opening of the female body. (00:49:46)
Answer: It is mentioned that Oberhauser died 20 years ago. This could have been many years after James stopped living with him.