The FCA willbe notifying all firms in the next couple of weeks to explain the three month period when they will be able to apply for full consumer credit permissions. These dates will depend on the permisions you require and your frm location. For the majority of mortgage brokers they will only need permission for credit brokering.
You can see the dates that apply for your firm in the FCA attachement linked here
Just scroll to page 9 to see the table and find your firm type from the list.