I measured this brisket in the thinnest part of the flat to prove the point (no pun) but you should always measure for doneness in the thickest part.
As you can see, this brisket is 25 degrees cooler in the thinnest part. It defies logic as the thick part should cook slower. I'm sure that could be very confusing for some people and it was for me for quite a while.
The fact is, the point is much thicker but it has a much higher fat content. Fat cooks much faster than muscle so obviously reads at a higher temp earlier than the flat. Mine is stalled out so it's even more obvious. They will start to creep closer together as it comes out of the stall but the point will always be done sooner and read higher than the flat.
So, stick a probe in the thickest part of the flat and ignore all other readings until the flat is like butter (190-200 usually)