This is my first time raising chickens and I'm very confused about when to switch feeds and what to switch to. I've read and been given lots of differing advice and wanted to see what everyone here thought. My girls are just now 17 weeks. I've been told to switch to layer feed when they turn 18 weeks whether they've started laying or not, to wait until they start laying, and to not switch to layer feed at all...to use a higher protein feed such as feather fixer or all flock and offer oyster shell with it. I've also been told that when I do switch to mix it in with their current feed to start with. HELP!