I am sharing with you the last Brexit update received from English UK and have copied below the most important part which is telling us that until at least the end of 2020 there will be very few changes.
Hope this is helpful.
„Entering and leaving the UK after 29 March 2019
From 30 March 2019 until the end of 2020
There will be very few changes for students travelling to the UK after Friday 29 March 2019 until December 2020. During this time, anyone from the EU or EEA can enter the UK exactly as they do now (differences depend on whether the UK signs a deal with the EU).
If there is no deal, anyone who wants to stay for more than three months will have to apply online for a European Temporary Leave to Remain, which is valid for three years.
These will be accepted for entry to the UK until December 2020.
If there is no deal, ID cards will be accepted for entry until December 31 2020. If there is a deal, there will be a „transition period“ while laws are being changed and ID cards will be accepted until the end of 2020. This means there is plenty of time to plan for when passports become necessary in 2021.
Travel to the UK from 2021
From 2021 it will also be easy for students to enter the UK and we look forward to welcoming European students to the UK as we do now.
EU and EEA students coming to the UK will have to apply for an Electronic Travel Authorisation (ETA), which the UK Government says will be cheap and simple to do. When they arrive, they will be given a short-term study visa.
Young adults may also be able to come to the UK on the Youth Mobility Scheme, which would allow them to stay for longer and work while studying.
Travel from the UK
If you have students who are already studying with you and planning to travel around Brexit day, 29 March 2019, they should be given a letter which confirms their enrolment and their start date.
Showing this letter when they return to the UK will mean they do not get a three-month entry stamp on their travel document and won’t have to apply for European Leave To Remain.“