You can take a flu shot now also. Winters have not started in full bloom yet and so the flu conditions. Your body will get the required immunity within 2 weeks. The ideal time to take the vaccine is early October though.
You need Twinrix if you are suffering from Diabetes or chronic liver disease or HIV.
Otherwise childhood vaccination of Hep B is sufficient to provide immunity even now. Hep A vaccination should be done only if you have not received any vaccine earlier.
All inactivated vaccines can be administered on the same day, or on any day before or after giving other inactivated or live vaccines. However, if two live vaccines are not given on the same day, they need to be given after 4 weeks interval.
Twinrix and Influenza vaccines can be taken on same day or spaced as you are comfortable.