I clicked on the article in order to understand the reasoning behind this change, especially at this time where the cold weather is especially harsh for a portion of Ukrainians without electricity/heating:

Announcing his signature on the bill, Nawrocki, who is aligned with the right-wing opposition and regularly clashes with the more liberal ruling coalition, claimed credit for pushing the government towards ending the “unconditional privileges” granted to Ukrainians.

No reason. Just another fascist undoing policies put in place by human beings with a bit more sanity.