What should my next step be after qualifying for CPT exam? Should I join a coaching or would self-study suffice?

Right after the declaration of CPT result start preparing for IPCC as you have only 9 months of gap available and for that I would suggest you to self-study with institute's material. You can also go for a good coaching institute.

Whether Self Study is possible? Yes, totally possible. Whether Self Study is feasible? No, you run out of time, if you are giving the immediately available attempt after CPT, since 9 months are not enough. Whether Self Study is recommended? No, at IPCC level, I won't recommend Self Study. At Final l