If you are already VAT registered in an EU member state and you are not using a warehouse there in principle you can de-register from this country and only declare your return in the OSS. 


Different rules might apply for different countries regarding the deregistration. In some countries, it may still be necessary to submit an annual VAT return for the first half of 2021, so that deregistration can only take place at the end of 2021. Please contact GVC for a more detailed assessment for your situation.