head of the department has been given authority to take a decision when an application is received from an official seeking exemption from poll duty.

“If prima facie, the head of the department finds the official is fit to do election duty, then the application could be rejected there itself saving the medical board’s time. However, if the head of the department feels that a medical assessment is necessary, the application is then sent to the medical board for examination. The report of the medical board will be treated as final for accepting or rejecting the application,”

pregnant women and officials reaching the age of 59 can exempt themselves from poll duty without any medical assessment.

Yes this notification is true and election commission of India has published it. The application has to be given to your departmental head and he will grant you exemption.

Regards 

She can give an application to district collector along with the authority who has engaged her in election duty seeking exemption on the medical grounds and cancellation of duty,

Yes lactating mother and pregnant women are exempted from the election duty but as your mother is in job and she is only 59 years of age she has to produce the medical certificate of the inability to go for election duty and this should be exempted by the Election Officer at the district if it is not then she has to go for the election duty

You can submit the same to her departments and election Commission or it's office to show her inability to attend it on medical grounds

1. It is true that they can be exempted.

2. Has she sent a representation to state that she be exempted on account of the reasons mentioned by you? If it has been given then she should wait for the relieving order and then file a writ petition in the High Court to set aside the order of joining election duty.

She is a senior citizen and having medical problems, she can give a letter requesting to relieve  her from such duties to the district collector's office where the duties of the election are being managed.

You take her to the office for submitting the letter