It depends on your sponsor,if the company is sponsoring your family visa and in your offer letter they mentioned this,then they can do the family visa processing after RP,
6 months bank statement may not be mandatory in this case.
They can do it with 3 months or less! also .In general if one is calling his family with his sponsorship then i think
6 months bank statement is required.So contact your sponsor
company mandoup for details .I have seen my friend calling his family within 3 months after he arrived qatar .