It is very difficult to draw clear conclusions. Doing all kinds of assumptions and math using the stint data my take is Ferrari appears to be ahead of Mercedes with around half a second and Mercedes ahead of Red Bull by around 2 or 3 tenths. I may be completely wrong in that assessment. Based on historical data I believe Ferrari were running lighter compared to Mercedes and Red Bull which is also something I have considered in above opinion. Go easy on me.
Hamilton struggled all morning. Mercedes had trouble pushing the car but by the end of the day was in a happier place for long runs. It was still not great when pushed for single lap. Hamilton used slightly higher engine modes or may be lesser fuel I don't know. Russell used the same mode in the stints that I have picked. For the whole day they stuck with C3 compound.
Ferrari had even performance throughout the day on both longer runs and on single lap when pushed. For the most part Ferrari used C3 but also switched to C2 in between. Their engine mode was the same across the day which seems like it was one step higher than what Mercedes and Red Bull were using for stint runs. Unless their new engine is better than the others.
Red Bull kept alternating between some higher engine modes and slightly lower ones. Except for one single stint on mediums they kept using C2 and used C1 for the last part of the long stint.
I only used the lap times from the evening session as the cars were settling down and eliminated some odd laps in the stint.
Stint Averages
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Ferrari (C2) - 1:38.4xxx
Mercedes (C3) - 1:39.6xx
Red Bull (C2) - 1:40.1xx
Lap time data from @f1debrief