I have always mixed wheat in but when we ran out of pellets recently I filled a couple of bins up with straight wheat and found they wer scattering less food under the bins in their search for pellets, so im going to switch one bin at a time from now as you say.
Do you provide grit to aid the change? wer on the edge of a grouse moor so going to borrow a few buckets of grouse grit, good idea?
They get grit right from the minute they reach the pen mate. Just dump a couple of bags(obviously depends on numbers of birds) in 2 or 3 places around the pen and they'll scrape and peck away at it.