It's hardly last minute advice. Last minute would be the day before your AS exam.
I crammed for my subjects, expected C's/D's and came out with AAB for AS, but that is because I did essay subjects probably. It was very stressful nonetheless so I definitely do NOT recommend this way regardless !!!
Since you picked really hard A Levels, If I did your subjects and I crammed for that I'd have failed lol, so you have to work exceptionally hard for them if you want the top grades.
All of your subjects except Maths are linear, so when/if (schools have the option now) you sit your AS exam in Bio, Chem and Psych it wont count towards the final A Level and you have to do the AS content again in Year 13, so you need to bear that in mind.