Amendment of the Act on Entry
On January 1, 2021, the Act amending the Act on the entry into the territory of the Republic of Poland, the stay and departure from this territory of the European Union Member States and their family members, and some other acts, submitted by the minister, entered into force.
As we can read on the website of the Office for Foreigners, the act adjusts Polish law to the provisions in force in the European Union as regards the rights of EU citizens and their family members to move and stay freely within the territory of the Member States. New legal bases concerning refusal of the right of residence and the right of permanent residence were regulated. The amendment also ensured that Poland would apply the agreement on the withdrawal of the United Kingdom of Great Britain and Northern Ireland from the EU in the case of the residence rights of British citizens and their family members.
Source here