I know next to nothing about the UGCC. Can you explain what they mean here?

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Our consecrators were those who became bishops in the time when our Church was liquidated by the betrayal and Communism.

For a long period of time, under the Soviet Union, the Greek Catholic faith was outlawed. The communists couldn't entirely outlaw the Roman Catholic, or Eastern Orthodox churches, because they were simply to large to liquidate without massive rebellion.

However, the Greek Catholic churches were particulary targeted because of their Union with Rome, and small enough to outlaw without much resistance,. The communists particularly despised the Greek Catholics who they viewed as as "subversives" because to the communists, they were just the same as the Eastern Orthodox, however, they pledged allegiance to a western power, the Vatican. It was only until after the fall of the Soviet Union, that the Greek Catholic faith was again legalized.