Given your JEE Main Paper 2 percentile of 85.3 and a 75.6% score in Class 12, along with your SC category status, your prospects for admission to recognized architecture programs look quite promising.

The reservation for SC candidates does, in fact, offer a notable advantage, as the cutoffs for this category tend to be less stringent compared to the General pool. So, statistically speaking, you stand a good chance.

For B.Arch and B.Planning programs, participating in JoSAA counselling is essential. Based on trends from previous years, you could be considered for seats at institutions such as:

- NIT Rourkela

- NIT Hamirpur

- MANIT Bhopal

- NIT Raipur

- Potentially NIT Calicut during the later counselling rounds

It is advisable to remain engaged throughout all the JoSAA counselling rounds, as seat availability and cutoffs often shift in the final stages, enabling more candidates to secure desirable placements.

Additionally, since you are appearing for NATA, this will expand your application opportunities. With a competitive NATA score, you would be eligible to apply to Schools of Planning and Architecture (SPA Bhopal, SPA Vijayawada, and possibly SPA Delhi) as well as reputable state and private institutions such as CEPT Ahmedabad.

Furthermore, if you clear the JEE Advanced examination, you will be eligible for the Architecture Aptitude Test (AAT) for admission to the B.Arch programs at IIT Kharagpur and IIT Roorkee.

To summarize, your optimal strategy would be:

- Apply via JoSAA using your JEE Main Paper 2 score

- Appear for NATA and utilize COA/NATA counselling

- If eligible after JEE Advanced, attempt the AAT for IITs

- Explore state-level counselling for institutions accepting NATA scores

If you have an anticipated NATA score, I can compile a more targeted list of institutions for you. Best wishes for your upcoming examinations and application process—you are certainly on a promising path.