is it illegal to get relieved date and joining a company same

This should not be an issue at all since Company Y did not bother.  In any case, if Z company asks, you can always explain the position. That's all to it.

There can be no such provision.  If they do terminate on this flimsy ground, then you have to deal with it.  In any case, once the earlier company Y has not bothered, and such overlap of working days will not be there between Company Y and Z, I dont think there will be any such issues.

Premature query, without any problem.

You may raise query with reference to some specific problem, if and when arises to find solution for that.

However, even if for your information some type of problems are mentioned, what could be the remedy with you to sort out that?

Premature query. Ask solution for some specific problem, if and when arises. Even if you are informed about the nature of problems that may arise, what will be the remedy with you to sort out those problems?

If you start worrying in this manner you will never be able to sleep throughout your life.    Generally for leaving and joining purposes in Government, there is the concept of "Forenoon, FN" and "Afternoon, AN. If a person leaves the establishment in the FN he will not get salary for the day. If the person joins another department in the AN he will get salary from the next day only. Thus a person getting salary from two places for the same day will rarely arise. Thus when a Government servant is transferred from one department to another double payment and non-payment are avoided.

Very well advised.

Hello R.Ramachandran Sir,
 

I am also having 2 days overlap between my first and second company and since it was first job switch for me and was not knowing about the consequence.

I din't notice and also my background verification went green in my new company.

Its been 7 month and was unnoticed. I tried to transfer my PF then I got stucked so asked my new company HR. she asked me it is because of overlapping date and i should go back to old company and ask for correction. I went and requested but they said it cannot be changed as my account had been closed.

i informed the same to my current company and they later initiated the correction process but the legal team of the company said that legally there is no issue since my current company doesnt fall under dual employment policy and ket it remain unchanged. In regards to my PF transfer, both companies agreed to help me out either in withdrawl or manual transfer.

Now sir my question is if i go to company Z, then will this problem impact me in background verification ?

company Z will consider my issue or it will always be an issue for me in job search ?

Generally for Government employment they follow the concept of forenoon and afternoon for joining or leaving employment.  If you join a company in the afternoon you will not be eligible for payment for the date of joining. If you leave a company in the forenoon you will not be paid for the date. Thus getting paid from 2 places for the same date is avoided. But generally those who are responsible to get you signed in or signed out do not care about the FN / AN business.

Whether you did what you did knowingly or unknowingly it is a very trivial matter and you should not worry about it.