Company asking for pre dated ipr declaration

You are just an employee, and as an agent of your employer, you are working with a client.  You are a stranger, and you are responsible for your employer and not to his client.  Inform the facts to your employer and also take legal opinion in writing from the employer's advocate (panel)

Yes, apprise your employer of the development and seek their directions.

You should keep employer in confidence and disclose facts.

Thanks for your reply. This is in sync with the employer. But I am not sure, if employer is really protecting me and thinking it through.

1. The document is predated to 2016, and i am being asked to sign it as if it was signed in 2016.

2. The clause to IPR is already signed between me and my employer, how can I sign it with someone else ? will it be not in conflict. IPR is like property as I understand it which cannot be sold to 2 persons.

3. This will expose me legally to client directly ? should I allow my employer to let me do that ? shouldn't the employer protect me from any legalities from client whatsoever ?

My understanding you should recall if you have executed any agreement in connection with the services you will provide to to your employer and if you have then your further action depends on the terms of that agreement. Since my understanding your position is a third party.  Hence liability in this case depends.