https://india-visas.org/indian-ebusiness-visa/
e Business Visa India is a double entry visa so you have a permission to stay up to 180 days from the date of entry in India.If you are an eligible citizen then in 1 year you can obtain a maximum two visa.
If you want to stay more than 180 days then you need to apply for a consular visa because e-visa for India is not extendable.

If you are e Business Visa India holder then you can arrive through one of the 28 designated airports or a seaports which is 5 in India.
You can leave the country from any of the authorized immigration check Posts in India if you have a e-Business visa holder.