Why is Eugenia Semyonovna Ginzburg awakened early in the morning on December 1, 1934 in the nonfiction book, Journey Into the Whirlwind?

Eugenia Semyonovna Ginzburg is awakened at four in the morning by a telephone call on December 1, 1934. As a loyal Communist, Ginzburg actively serves the party as a teacher, and her husband Pavel Aksyonova works for the Tartar Province Committee of the Communist Party. The telephone call directs her to report to the regional committee office.