When to switch from starter/grower to layer feed?

[AZ RT89A]

My chickens are approaching 5 months old now, I had read to keep them on a started/grower feed until they were ready to start laying, and I just found my first couple eggs today. Should I switched them right over to a layer feed or something else? I have about 50lbs of starter left, should I mix that in with a different type?

 

[Mutt Farm]

Howdy! You don't ever need to switch if they have oyster shell free choice. Hopefully, they have had that available already. You can keep them on what you have, just be sure they have the oyster shell for added calcium needed to make hard shells. If you do switch to layer, don't do that until all hens are laying.

 

[ChickenCanoe]

Mutt Farm has good advice.
When I have an entire flock laying, I prefer to feed layer since it is formulated to get the best production (protein, vitamins and minerals)
You can also mix layer with the starter to use it up. Mixing layer with starter 50:50 you'll be feeding approximately 2.5% calcium.