I´ve noticed the first moult to take a few months to change the birds entire plumage. Crankiness is the top of the list of what to expect, though not all birds are as bad as others, some hardly cranky at all!
Offering plenty of bathing opportunities can help sooth the itchiness of the pin feathers. Some birds will even allow you to gently preen them, but not all, and sometimes they may decide mid-preen that actually they don´t want you to do it any more and try nipping you