bromeliads live through the water stored in their "cup" so you don't have to worry much about repotting them ^.^ As for the
flower, it lasts around 6 month and then dies off. During the time that the
flower is there, it'll have babies sprouting around the edge of the "mother
plant" After the
flower dies, you can wait for those little baby
plants to get good and established and put them in different pots if you wish. Don't keep the soil too wet though. They can survive in dry soil, and ya. Their roots are basically only there to keep them in the ground.
Good luck!
~Phoebe