I had a similar not so dramatic incident with on a Air China flight out of PEK in a 744 three years ago. As a pax. Plane was already accelerating pretty much, when it made an abort. Pretty hefty and impressive.
You could imagine that there was no decent info why and what. After the runway was cleared and a/c parked, we waited and I noticed mx in and out and on one of the engines. Found one of the pilots and he explained in english, that the Amber light came just after the acceleration. Great they could abort.
Of course, sensor issue, rev locked and after the usual paperwork back to runway.
Great work, but nobody except me knew really what it was. This is China. And a very new 744.
Danny