Bonus payment under amendment act 2015

There was no Separete Registration was prescrbed for a establishment under The Payment of Bonus Act 1965.

Since your have not mentioned whether the salary includes all allowance and perks etc. Please ref definition of Salary to be considered for Bonus calculation purpose - 

For the purpose of calculation of bonus a salary or wage includes a basic salary or wage and dearness allowance but does not include other allowances, overtime salary or wage, house rent allowance, traveling concessions, bonus, employer's contribution to provident fund, retrenchment compensation, gratuity or commission. {Section 2(21)}

Considering the retrospective applicability of Amendment Act 2015, w.e.f 2014-15, whether necessary to pay to employees whose salary less than 21,000 for FY 2014-15 now.

Many  High Courts have given stay to retrospective amendment of the Act.

1)Through this amendement some more employees are eligible for Bonus , Is it necessary to pay Bonus toresigned employees who have worked more than 30 days in FY 2015-16.

2)Whether other establishment include service sector private limited companies Or Bonus is applicable to manufacturing industry alone.