Christian Klien on Thursday said it has not been decided if he will drive during the opening practice session in Turkey.
Soon after he was appointed as a reserve and Friday driver by the HRT team, Austrian Klien drove in morning practice in Barcelona.
It then emerged that HRT's other reserve driver, Japanese Sakon Yamamoto, would likely be in action on Friday morning in Turkey.
"All four drivers will be in Turkey," Klien, 27, said, referring also to race drivers Karun Chandhok and Bruno Senna.
"Who gets to drive the Friday practice is a decision entirely left to the team management after weighing all factors," he explained.
"Track time has become a scarce commodity. And the test ban hurts a new team even worse than the established ones," said Klien.