Increase the number of workers - register as per act or need to extension of existing registration?

Context : Manufacturing unit
As per given details
Daily 149 workers already they have permission from factory license act
Currently operating 3 shifts
Shift A / Shift B / General shift
Problem : Now he have to increase the number of workers for his unit due to requirement ..
His doubt ?
Either I have to hire new one incase
( What rules as per factory act need to follow. Incase if I want to increase 30 workers ... shall I register as per act or need to extension of existing registration ,only )

Recruit the workmen. Inform the Inspector of Factories in FORM -2
(Prescribed under Rule 4 and 12) for increase in number of workmen along with required fee for amendment of your licence.