RB is set to start the Austrian Grand Prix weekend with its Formula 1 cars running in split specifications to understand why its Spain upgrade package failed to deliver.
The Italian squad sought to consolidate its sixth position in the constructors' championship and close the gap to Aston Martin in the points with its wide-ranging updates.
The team added revised sidepods and a new engine cover to the VCARB 01, along with a new rear wing and floor, in a bid to extract more performance over the triple-header.
But the upgrades failed to deliver the hoped-for step at Barcelona; Daniel Ricciardo finished 15th and Yuki Tsunoda was 19th as the team failed to score.
Speaking about the plan for Austria's sprint weekend, Ricciardo explained that the team needed to explore the new parts further.
In practice, he is expected to run a handful of the new parts, with Tsunoda running others by way of comparison, blended with a series of new parts lined up for the Red Bull Ring round.
"There are still some questions for sure, but are we convinced that the upgrade was a flop? No, we're not," Ricciardo said.
"Yuki and I are going to start with different set-ups. It's a combination of everything and because we're still trying to figure it out.
"We'll start different [Friday] morning and hopefully learn a bit from practice and then kind of merge for the sprint quali.
"But yeah, we're not chucking anything in the bin yet; there is still no firm conclusions I'd say.
"It's a bit harder now obviously on a sprint weekend, but we have to keep trying to plug away at it.
"It's a bit of a mix. There is certainly some old bits on one and whatever, but it's not just like for like.
"Because there's even some new bits I think, which we're both going to get a little piece of."
Tsunoda revealed that the Spanish GP data showed the team what it expected from the new parts, but ultimately could not account for the overall lack of performance.
He felt that it was a "bit of a mystery" that there was a disconnect between the data and the performance, and hoped for a clear answer to emerge after the sole practice session at the Red Bull Ring.
"I hope I have a clear explanation into this week, but obviously the team is digging into that problem very hard," the Japanese driver said.
"We still see what we wanted to see on the data after the race, but somehow it's not performing well.
"We saw a couple of things that might cause it, but there's no still clear answer, so that's a bit of a mystery for us.
"Obviously [there were] a couple of things that we could have done better on the set-up side or whatever.
"But [it] still doesn't explain why we lost as much as that compared to previous races."
