Ah.... you will be pleased to hear that fitting Pitot covers is now a mandatory procedure with Astraeus for anything longer than a few hours on the turnaround.
Lest you think this is some third world problem, I once tried in vain to programme the FMC at a certain French location before air testing a 757. Various anomalies cropped up including a 135 knot speed variance between the ASI's on the ground, resulting in the aircraft logic assuming it was airborne!
The FMC responded by only allowing inputs as if the aircraft was in the air.
Turned out that a swarm of bees had crawled into the Pitot system and died. The seal that resulted trapped air that merrily expanded in the heat of a Southern French summer, interpreted by the ADC as 135 knots.
We enquired of the well known pan european maintenance organisation whether thay had fited covers to the Pitot system.
"Of course" they replied