Most Ficus come from wet-dry tropics, Where they have only 2 seasons, the rainy season and the dry season. I have a ficus that went 4 months bone dry one winter. I started watering again in spring and it came back to life. Ficus with thick, fleshy trunks store a lot of water. For these "ginseng ficus" types, a 2 or 3 month dry spell is not a problem.
However, Ficus are evolved for ONE dry spell per year. Once they start growing again, you don't want a second drastic dry out too quickly. That second dry spell in a few months can be the killer.
Once they are growing they want frequent water.