out of curiosity, do assessors get assigned specific questions to mark, or do they mark entire papers? because i've heard both!!
Ive heard both too, for the subjects ive heard about
Biology marking is done online and an assesor goes question by question i.e marks a question from 50 students then moves onto the next question.
For maths, spec and methods ive heard its done with a hard copy and examiners would go through a paper at once (apparently they mark spec/methods exam 2 in 8 minutes

) - may be outdated
Typically an assessor will be given a set of paper to mark. After the 1st Assessor has finished marking them, it will then be referred to a 2nd assessor to ensure consistency across the board. Which will then determine a student's mark and typically their is some variance in mark allocation, but not a lot.
What happens if they disagree on the mark by a large margin
Assessor 1: Gives Student A 9/10 for Question 1
Assessor 2: Gives Student A 6/10 for Question 1
If this happens, they will deliberate between them on why they gave what they gave and hopefully reach a consensus to a mark they both agree on.
If they don't ,it gets referred to the Chief assessor who will determine the student's mark on that question.
More information on marking can be found here
Hmm each assesor doesnt know what the other assesor gave for subjects like english if the discrepancy is too much it goes to 3rd assesor/chief examiner
For other subjects if one assesor gives 1/3 and the other gives 2/3 you will just get 1.5/3 for the question and then if the overall mark of your exam is too different it will be referred to a 3rd/chief examiner