Updated: 10:38 PM EDT March 31, 2021 COLUMBIA, Pa. — Vaccine providers in Pennsylvania are preparing for another wave of appointments after the state moved to Phase 1B and set up a timetable to make everyone eligible for the vaccine by April 19. Pennsylvania stayed in Phase 1A for three and a half months. About a third of Pennsylvanians—4.5 million out of a population of 12.8 million—were eligible to get the vaccine under Phase 1A. Pennsylvania has vaccinated about a third of its population—31.8 percent—according to CDC data. Now the remaining two thirds of the population will become eligible within a 20-day window. On March 31 vaccine appointments were expanded to include police, corrections officers and other law enforcement; volunteer and professional firefighters; grocery employees; and food and farm workers.