Formula 2 drivers remain confused about why more than half the field restarted a lap down after a feature-race red flag caused by Ferrari Formula 1 junior Mick Schumacher.
Schumacher clipped the right rear of Tatiana Calderon's Arden-run car into a spin, blocking the track for the cars placed ninth and below.
The drivers who ended up lapped were in that position because they were reordered in the pitlane and put behind cars that had officially completed one lap more before the red flag.
This meant that the order of the cars was in line with the pre-red flag order, but those behind the top eight were showing as a full lap down.
As the timing system was not adjusted, these drivers remained lapped and were not allowed to unlap themselves under the safety car, as per the normal procedure.
Article 42.3 of F2's sporting regulations, which relates to the procedure for lapped cars when resuming a race, was not followed.
The rule states: "At the two minute point, any cars between the safety car and the leader, in addition to any cars that had been lapped by the leader at the time the race was suspended, will be allowed to leave the pitlane and complete a further lap, without overtaking, and join the line of cars behind the safety car which left the pit lane when the race was resumed."
No official explanation has been given but is expected once an investigation into the procedure under the red flag is completed.
Had the procedure have been followed, the top eight - who were all yet to pit - would have needed to stop again, which would likely have shaken up the order dramatically.
Some teams and drivers believed the timing screens would be corrected and therefore pushed hard as they thought they could make up positions.
Feature race winner Nyck de Vries, who believed he needed to build a gap at the front of the field over those who had already stopped, said: "We were forced to change tyres [under the red flag] to make a gap.
"If we didn't make a gap after the red flag we would have been behind the people who had pitted behind us.
"So we were forced to really push after the red flag to make a 25-second gap to the drivers on the alternative strategy who boxed earlier than us. We were kind of forced into that strategy."
Many of the drivers in the top eight now face a tyre shortage as they used an extra set to try to build the gap to the cars on the alternate strategy, and may have to use scrubbed tyres in Saturday's sprint race.
Points leader Nicholas Latifi told Autosport: "I honestly didn't know we were a lap down, I don't think the team knew 100% until the end of the race.
"I thought I was fighting for a reversed-grid [pole] and in the end I was fighting for nothing. If I was fighting for nothing I wouldn't have taken any risks.
"I was pushing flat out because I thought if I can get past these guys, maybe I could get on the edge of P8 or P9 after the others had pitted.
"For me, this is a mistake from race control which you have to analyse because I think something like this has happened before. "Even if they put the leaders to the front in the pitlane, just take a lap off for us [the lapped cars]."
Latifi was out of position on the alternate strategy, and had a number of incidents in the race with other drivers.
He was given a drivethrough penalty in the closing stages for causing a collision with Sean Gelael, and had his points lead cut from 26 points to just one, with de Vries taking over second in the standings.