Copiapo, Chile (CNN) -- Rescuers in Chile expect to reach 33 trapped miners as early as mid-October -- sooner than previously expected.
Crews could reach the miners between October 15 and October 30, Mining Minister Laurence Golborne said Friday. Officials had said earlier that it would be November.
The first test of a rescue capsule was carried out successfully Thursday.
Once one of the three drills working to reach the trapped miners breaks through, the rescue capsule will be lowered at least 600 meters (1,968 feet) to begin ferrying the men to the surface.
The Plan A drill reached a depth of 566 meters (1,857 feet) Friday, 34 meters short of the 600-meter depth needed for the rescue capsule. But the hole it is drilling still needs to be widened to 70 centimeters (27.5 inches) to accommodate the capsule.
The Plan B drill continued to delve steadily deeper, reaching 362 meters (1,188 feet), Golborne said.
And the Plan C drill -- an enormous oil drilling platform that dominates the rescue site -- had reached 175 meters (574 feet), he said.
The drill that reaches the men first will be used to pull them out, Golborne said, but a second drill could function as back up option.
Officials would not say which plan they believe will first reach the miners.
The men, trapped since August 5, have been surviving on supplies funneled to them from above ground through earlier bore holes, each about 4 inches in diameter.
The miners have been spending their days watching the news and movies on a small projector.
Many are also exercising by working out with a trainer, who leads sessions over a video conference system. Officials have said the exercise helps the men pass the days and also will assist several of them in losing weight so they can more easily fit into the rescue capsule.
Golborne said the technological advances with the capsule did not mean it is time for celebration yet, cautioning that the rescue is in its most critical phase and that congratulations will be given only when the last miner is removed.