Yes, that is true. Another thing to look for is the order of bleaching in yellow skinned birds.
"With yellow-skinned hens, such as leghorns, loss
of pigment from their skin is an important characteristic
for determining the persistency of lay. As a
pullet grows, yellow pigment is deposited in the
skin, beak, shanks and feet. Once the pullet starts
laying eggs, the pigment is then removed from the
pigmented areas to provide the yellow color in
eggs.
The pigment bleaches in a definite order - from the
vent, eye ring, ear lobe, beak (corner of the mouth
toward the tip), bottom of the foot, the shank (front,
back and sides) and finally the hock and top of toes
(see Figure 2 for the parts of the hen)."
http://www.ca.uky.edu/smallflocks/Factsheets/Evaluating_egg_laying_hens.pdf
Tamara