Phileas is right. Colleague of mine who pre-empted his flying career with five years in "ops" tells me that in the glorious past,the number of aircrew who "phoned in sick" , particularly cabin crew, on a friday night caused frantic aggravation for whoever was manning the crewing & ops depts. Later, most companies started demanding a "sick note" . One could get away with three days sickness without a note but not any more and certainly not in the companies I served. Skipper Props advocates just phoning in sick and telling porkies. That would have caused just as much aggro for this crew and suspicion would have been aroused anyway.