Not too sure what you're asking. You can take clones from a flowering plant, but it takes quite a while for it to revert back to a vegetative state. At times, a month or longer. Also, you really want to do as little cutting as possible when you're flowering. You don't want to cause much undue stress, which can lead to infections, slower growth rates, and the dreaded hermaphrodite.

If you're really far into flowering, you may just want to think about cutting your losses and growing out a healthy mother plant to take clones from. If you're just looking to preserve the strain, you could also think about revegging after harvest.