Tidying up all the added news from practice day in Shanghai, Michael Lamonato brings you his notebook from the paddock.

– The Friday notebook is brought to you by pulped paper, which is what my physical notebook now resembles after the rain that was forecast to arrive during practice arrived while I was outside during the press conferences, and it wasn’t a shower so much as a thunderstorm. What could’ve been…

– Though the occasional sprinkling of raindrops kept drivers on their toes in FP2, the real meteorological villain of the day, however, was the wind, which wreaked havoc. Max Verstappen and Stoffel Vandoorne had off-track excursions in the morning session, though none sustained any damage, and Lewis Hamilton spun at turn 11. Lance Stroll and Romain Grosjean also spun in FP2 on their qualifying simulation laps. Sergey Sirotkin lost his mirror, which is probably unrelated but nonetheless amusing.

– Stoffel Vandoorne stopped on track late in FP2 with an incorrectly fitted wheel in the latest of a growing line of pit stop problems. The team was summoned to the stewards to explain the decision and subsequently fined €5000 for the error.

– Though there is growing talk of making pit stops safer, there seems little real appetite to change regulations regarding pit stops.

– The ultrasoft proved especially brittle in China despite the cool conditions. Pirelli has brought the medium, soft and ultrasoft compounds, skipping the supersoft which it believes would’ve been too similar in performance to the soft to create interesting strategies. Some drivers, including Lewis Hamilton, commented they couldn’t get more than one hot lap out of them; Daniel Ricciardo said they were worth around four corners of performance before losing their edge. It seems they are at best a qualifying tyre.

– The fragility of the ultrasoft compared to the other more durable compounds will create a quandary for teams vying for a place in Q3. The ideal race strategy would be to avoid the ultrasoft, which would be good for a maximum of 10 laps, but given the closeness of the midfield, teams might be forced to adopt the faster tyre to make the cut — unless, of course, they perceive a benefit in starting just outside the top 10 on a superior race tyre.

– Red Bull Racing is pushing hard in its early-season upgrade programme, with Max Verstappen back-to-back testing a new front wing during FP1.

– Further to Daniel Ricciardo saying on Thursday that he would require a new energy store after it failed in Bahrain, his car has also moved to its second of two control electronics, edging him ever closer to a seemingly inevitable penalty.

– In perhaps a sign of confidence, Mercedes spent some of FP1 testing a Baku-spec low-drag rear wing. Azerbaijan usurped China as the grand prix with the longest straight — if you include the easy-flat turn 20, the Baku front straight is more than two kilometres long, easily besting China’s 1.6-kilometre back straight.

– Tomorrow’s forecast is for only a 20 percent chance of rain and a cool top of 17 degrees, with Sunday expected be sunny and relatively warm 20 degrees.

– Maurizio Arrivabene partly explained that the pit stop error that resulted in a broken leg for Francesco Cigarini, putting it down to a combination of human, mechanical and electronic factors. The team principal paid tribute to those who helped his team: “I would like to thank our team doctor, the FIA medical staff and also the authority of Bahrain that granted to us immediately the best doctor in Bahrain to do the surgery.”

– Arrivabene also shed further light on the commercial and regulatory negotiations for 2021, telling the Friday press conference that Liberty Media had given the teams an end-of-May deadline to finalise their agreement (or otherwise). Force India’s Bob Fernley was less committal, suggesting agreement could be staggered over the next year or so in order of urgency.

– Arrivabene was non-committal about the achievability of a $150 million budget cap, saying only that it is being discussed.