DAERA has recently published guidance on the internet in respect of exporting where the UK leaves the EU without a deal.  The link can be found here:
https://www.daera-ni.gov.uk/publications/guidance-exporters-products-animal-origin-poao-event-uk-exits-eu-no-deal-scenario

To ensure you get the correct support with your queries on DECOL, updated contact details are included below:

• If you have a query in relation to milk and milk product exports applications please contact dairy.export@daera-ni.gov.uk
• For all other commodities please contact the relevant DAERA Regional office.

Please ensure you advise your customers that if they intend to export the product they are purchasing, they must make an application via DECOL for the necessary export paperwork.  Links are included below:

Main page: https://www.daera-ni.gov.uk/landing-pages/exporting-animals-and-animal-products-northern-ireland

Meat and meat product page : https://www.daera-ni.gov.uk/services/meat-and-meat-product-exports