It's fine. If it's small enough chunks they might just go for it with no problems. If so grind it up and possibly mix it in their feed if they are not eating it when it's ground up.
It could actually extend it for a couple weeks. You can get them out of a molt though by jumping the protein up though. That helps them get out of a molt faster. You could but you have to wait or increase protein for a couple weeks.
I think it's because you're making it as if it's the first day of spring or fall. When daylight and night time are equal. Sometimes hens will molt as daylight gets shorter. Sometimes when it's fall which could have triggered it. You would have to extend daylight longer than nighttime by a few...
Welcome to BYC! Glad you joined the flock! What times is the light set to turn on and when is it set to turn off? When is sunrise and sunset in your area? Sometimes artificial light can kick them into a molt because it's summer again. My hens molt in the summer usually late July early August.