AS/A2 O/N session Registration Doubt

[Jugular]

Anyone know when the last date for registering in the October-November session is?
Also if I fill up my form for A2 first n submit it but later decide no resit some AS subjects is it possible to do that by filling in another form later?
Like for e.g. I fill up the CIE form for taking A2 Chemistry and Physics in the coming session, before getting my AS results, but in August when I do get my results for AS i see I did really bad in math and chemistry and want to retake them, is there a way of doing that by filling out another form? Or was it all had to be included in one form?

Thanks in advance.

[Freaked12]

Anyone know when the last date for registering in the October-November session is?
Also if I fill up my form for A2 first n submit it but later decide no resit some AS subjects is it possible to do that by filling in another form later?
Like for e.g. I fill up the CIE form for taking A2 Chemistry and Physics in the coming session, before getting my AS results, but in August when I do get my results for AS i see I did really bad in math and chemistry and want to retake them, is there a way of doing that by filling out another form? Or was it all had to be included in one form?

Thanks in advance.

July 19 is the last date for registration

and yes to your last question you can do that but you have to pay a 500 riyal penalty