Each broker is different in terms of offering and pricing plans. Here is some detail about popular brokers:
Upstox (RKSV) Unlimited Plan was discontinued in year 2015. They do not offer Upstox (RKSV) Monthly Trading anymore. Upstox (RKSV)'s new brand also do not offer UpStox Flat Rate Trading Plans.
Zerodha, the popular discount broker also doesn't offer Zerodha Fixed Monthly Plan. For Zerodha customers, Zerodha Unlimited Trading is not an option. Zerodha charge flat Rs 20 per trade.