Hi, thank you for your query.
As your ex-partner was granted leave to enter as a partner of a British national (you), his leave will only be valid as long as he is with you.
As your relationship has now ended, he had a duty to inform the Home Office: https://www.gov.uk/change-circumstances-visa-brp/youre-in-the-uk-and-have-a-brp
All you can do, which you have done already, is to inform the Home Office that you are longer together.
Your ex-partner is most likely going to have a problem when he returns to the UK either at the airport, where his leave to enter will be cancelled and possibly remove him back to India.
Or if he passed through Immigration, as he is no longer with you, he will receive a letter from Home Office cancelling his leave due to the change of circumstances in this matter.
Also, just as a side note, he cannot sponsor his wife from India as he does not have Indefinite leave to remain or is a British Citizen.
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