Pattern is written in British English (UK) terminology. (Pattern is mostly worked in US sc/UK dc but there is a stitch guide in the pattern.)
TOFT uses 100% house wool that easily breaks apart. Pattern directs to "break yarn" when yarn cutting is indicated.
There is a pattern modification for adding beads to the design.
There is a 12 day crochet along layout as well if you want to pace yourself or complete the pattern with friends.
Mod Note: While the pattern cover refers to Callista as Ed's Managerie Bird # 129, the Toft site refers to it as bird # 130.