Yes. True. AS level and A level are now separate qualifications.
So what this means is that, for reformed subjects i.e Psychology, History, Chemistry etc those sitting these subjects, planning to take them as full A level qualifications would only have mock exams this year as AS and A2 are no longer modular but linear. This means all of your real exams for the reformed subjects will take place in year 13. Your mock grades will only count to your predicted grades for when applying to university. In order to apply for uni, you need predicted grades unless you decide to apply after year 13 with your full A level results. So your mock grades do not count to your final grades; they are however there to aid teachers with deciding predicted grades for uni applications and for universities to see the academic abilities of students.
An example, If someone got E grades at their mock exams for History, Chemistry and Physics- they may be predicted one grade higher concerning their overall grade after year 13 so DDD . The EEE grades would not count to their real a level history, chemistry or physics a level qualifications meaning in their real exam, if they decided to work hard could receive ABB grades overall as those E grades do not count to anything but are merely mocks for predictions. So when applying to uni, they would get offers based on the DDD grade prediction.
In this case, if the person did do better than DDD prediction, receiving AAB or ABB the person could apply next year for better offers or 'better' universities or they could go through adjustment. Adjustment is where you've achieved higher than your predicted grades and you call universities to see if they have any spaces for the particular course you're interested in.
Hope this helps and makes sense, please feel free to ask any more questions x