UPDATE: Aitken's RP Motorsport entry was found to be outside of the series' technical regulations during post-qualifying checks.
He will, however, start the race from pole position under appeal.
The area of contention is understood to be a sidepod modification in front of the rear wheel, with a part of the bodywork that is usually vertical reported to have had a slight curve cut into it to create space for the exhaust exit.
"The decision will be suspended, as the team has decided to compete on appeal. Jack Aitken will therefore be allowed to start from pole," Jordi Castells, Sporting Director of championship promoter RPM, told Autosport.
"But according to the international sporting regulations, if Aitkins wins, or finishes in the top three, he will not go to the podium.
"The Spanish Federation will have to make a decision on this, which will probably be in the next three weeks.
"We can certainly say it isn't a modification that will bring, for example, a second a lap, but it looks like it doesn't conform.
"The team have said the sidepod was like that since they acquired the cars from ISR."
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