The government alone is responsible for deciding the date of assembly sessions and the governor has to sign the summons order.
However, according to Article 174 of the Indian Constitution and the previous judgments given by the Supreme Court, the session date is decided by the cabinet and the cabinet is not bound to state the agenda for the session.
The government alone is responsible for deciding the date, and even if the change in date is suggested by the governor and the government plans to stick to its date, the governor has to sign the summons order.
The governor has no power in the matter of summoning the house if the chief minister enjoys the majority in the house, and therefore, is bound to act on the advice of the cabinet.
In case the governor has reason to believe that the chief minister has lost his majority, the governor can use his discretion in fixing the date for summoning the assembly where the chief minister has to test his/her majority.