Clarification required regarding Control of Authority of Gratuity

GRATUITY ISSUE – CLARIFICATIONS REQUIRED:
Our Company XXX have his Head office Mumbai started in the 1960s. It started making molasses based chemicals at Maharastra and it was closed in the 1990s. XXX started another company for different products at Madras in 1972. In the 1990s it added some other products same complex. In 2002, the name of the Company was changed as YYY. So 2002 onwards XXX have their Corporate Office at Mumbai and the manufacturing facility at Chennai. This manufacturing has been closed by Dec-12 and it obtained the permission from TN Labour Ministry to close the company and agreed to settle the employees by paying compensation after selling the land We, 84 officers, are approaching Control of Authority, Labour Commissioner office., Chennai.
1)We are not clear whether we should approach the Control Authority of State or Central Government since Head Office is at Mumbai and Factory was at Chennai. The company has got no other business unit.

2)Also, we, the officers ( Management Category), were eligible for 30 days of Gratuity per year of Service as per appointment, promotion letters and even by the letter given by the Chairman after closing the Company. Can the Gratuity Control Authority get us 30 days Gratuity or only 15 days Gratuity as per Act?
Can anyone clarify the above two points?

Gratuity entitlement is 15 days per six months of service but management is at liberty to pay more.
In this case, company has committed higher figure in writing.
Q1 is not clear.

Payment of Gratuity Act is an establishment based enactment therefore you have to apply for gratuity in the place where you have worked. If you are entitled to higher amount of gratuity, it is payable as per the concerned agreement. However, if the PGA Authority awards only 15 days completed year of service gratuity, you can enforce the agreement by approaching the appropriate govt for payment of remainder amount of gratuity.

In your case the Appropriate Authority is Central Govt. You can approach the Central Labour Commissioner because you have an office or factory outside one state.
If the terms of appointment says that managers are eligible for 30 days gratuity, you will get it. The appropriate authority can not say that he cannot pass an order for payment of 30 days gratuity because the law states that there is no bar on any employee to get a more beneficial amount.

I beg to differ from the view of my learned friend Mr.Madhu as regards the Controlling Authority for the purpose of disposal of the claims of gratuity of the employees of the factory at Madras since closed. Though the Company has its registered office at Mumbai which may be an establishment under the State's S&E Act, when the occasion for the claim for gratuity arose it has got only one factory that too in Tamilnadu which alone is closed and not the entire company. Besides, it's only manufacturing unit at Madras was closed with the permission of the Govt of Tamilnadu being the appropriate Govt under the ID Act,1947. The claim for gratuity arises out of the closure permitted by the Govt of T.N and the assurance given by the management before it only. Therefore, I would recommend the employees of the closed factory at Madras -
1) Have to approach the Controlling Authority appointed by the Govt. of T.N which also happens to be the app.Govt under the P.G Act,1972.
2) Sec.4(5) of P.G Act,1972 upholds the right of the employees to receive better terms of gratuity under any award or agreement or contract with the employer. Therefore, in case of back off , if any by the Company as of now, the letter of appointment, if it contains such a better term, can very well be treated as a contract and higher amount of gratuity can be claimed.