In the event of no deal, EU citizens will be able to enter the UK to visit, work or study after 29 March 2019 (may also apply to new exit date on 31 December 2020). For stays longer than 3 months, European Temporary Leave to Remain will be required.
The UK withdrew almost all of its no-deal planning notes in January 2020. However, they may be re-instated on the same or similar terms with respect to the 31st December withdrawal date. Most of the issues with which they deal, would be equally relevant to both a "no-deal" scenario or a "skinny" trade agreement scenario, one or other of which seems to be inevitable as and from 1st January 2021.
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