In the Airbus brochure (more like a book) Getting to Grips with Aircraft Performance, the standard climb profile for the A320 family is mentioned as
250 kt / 300 kt / M0.78
With this accompanying chart:
(image taken from Getting to Grips with Aircraft Performance by Airbus)
So these speeds (the first two phases) are certainly IAS.
The book mentions the reason for the initial 250 kt to be due to ATC restrictions <10k ft. I ran a search and found this to be true.
However, very ironically, this website (eurocontrol.int), gives the following figures:
290 kt / 290 kt / M0.79
(image taken from eurocontrol.int)
As visible from the chart, even this source clearly states that the speeds are in IAS.
Can someone reconcile this conflict: How can eurocontrol.int claim that the A320 flies at 290 kt under 10k ft, with Airbus's own book claiming otherwise, and why do these sources differ (250/300/0.78 vs 290/290/0.79) ? Which profile is more accurate to what real pilots fly?