The A318/A319 Professional Airbus pack for P3D4 has been launched by Aerosoft. Reduced prices can be applied : if you either had the previous A318/A319, or the A320/A321, then you’re eligible if you purchase the A318/A319 for P3D4. If you had the bundle A320 Family, then you should better order the A320 Family Bundle Professional for P3D4 now, and in a a few weeks, Aerosoft will add the A320/A321 pack download links.
Not all features are already included, so check Aerosoft forum for an updated features list. Some of them will come in the next updates and service packs.