When you create your first VAT return you will be asked to enter the start date of the VAT period you wish to submit for. After this first VAT submission, you will only be asked to enter the end date of the VAT period.
If the last period you submitted VAT for is in the past and you wish to bring your VAT submission forward, you will need to create a VAT return from the last period and up to the day before of the period you wish to submit for. For example, if you require to submit a VAT return from 1st January 2019 but the start date in the software is 1st July 2018, you would need to create a VAT return up to 31st December 2018. Once created, you will then be able to create the VAT return from the date you require.
You may also need to adjust the VAT reconciliation date to ensure any earlier transactions are not picked up in the new VAT return. You can edit the reconciliation date by going to Settings> Advanced Settings.
If the dates on your VAT return are incorrect and you are unable to delete the start date or follow the steps above, please email the support team at email@example.com.