Dear Ma'am,
I am writing this letter of resignation to formally notify you of my decision to resign from the post of Assistant Manager operations with XYZ Group of companies. I have taken this decision after through deliberation and assessment and I believe it is in my best interest to move on.
As per company policy, I would be required to serve a notice period of one month starting from today i.e. July 20th 2016 and ending with my resignation coming into effect on August 20th 2016 . Kindly relieve me of my responsibilities as early as possible to ensure a smooth transition for the organization.
I wish you and the company success at future endeavors.
Regards
ABC
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