Every party that isn't in government is by definition an opposition party. You're mixing up the criteria for recognition of the LoP of a house with what an opposition party is.
There is a strong bias in your previous posts and your submissions against the ruling party in India, which has been time and again questioned/ pointed out in your previous submissions. Not that there is anything wrong about it, but again HN may not be the place for political and potentially controversial discussions which can devolve into a flame war.
edit : fixed verbiage.
My posts are about democracy in one of the largest countries of the world. I feel democracy is one of the top area of interest to fellow hackers.
Lastly, AAP is not a regional party. In December 2022, after Gujarat Legislative election, Aam Aadmi Party has fulfilled the criteria for being the 9th national party of India. It is in the middle of the process of getting the official recognition as the National Party by Election commission of India.[1][2]
[1] https://www.telegraphindia.com/india/aap-becomes-indias-9th-...
[2] https://en.wikipedia.org/wiki/List_of_political_parties_in_I...