The United Kingdom (UK) formally left the EU on January 31st, 2020 following a Brexit referendum in 2016. The exit agreement entered into force on February 1st, 2020. Until December 31st, 2020 the UK is in a transitional phase during which EU law and EU regulations will remain applicable. There will be no changes for EU nationals in the UK until the end of 2020.
Please note, however, that the freedom of movement between the United Kingdom and the European Union will end on December 31st, 2020 and that as of January 1st, 2021 the United Kingdom will introduce a new immigration system. Students from the EU who have already settled in the UK before December 31st, 2020 have to apply for the “EU Settlement Scheme” to secure the rights associated with the "settled status" or "pre-settled status". Please note that this application cannot be made from outside the United Kingdom. Students from the EU who intend to come to the UK to study after December 31st, 2020 must apply for a student visa.
On the OeAD website you will find collected information on Brexit.