Payment of Gratuity should be applicable from day one so long as there are minimum of 10 employees in the company. If the above is fulfilled your period has to start from the day one at Partnership Firm. No other agreement to the effect is ever required for this Act.
Thanks and Regards
23rd November 2018 From India, Hyderabad
One should check the record of LLP, what date(DOJ) they maintained against each employee worked in that partnership firm.
25th November 2018 From India, Mumbai