EAD from OPT to C9

[Ademance]

I'm applying for adjustment of status, I have a current EAD which will expire in 08/19 under category C03B which is for students OPT, now I will apply for a new EAD under category C9, should I put on form I765 that I am renewing, or applying for a new one? as initial permission to accept employment. Also, Should I stop working once I sent my AOS, or can I keep working until my current EAD expires, or my AOS is received?

Thanks for your help

[newacct]

initial permission to accept employment

you can keep working until your EAD expires