Liberty Media has made no secret of its intention to extended the Formula 1 calendar, potentially up to 25 rounds.

The 2019 F1 calendar will feature the same 21 races as this year. Last week F1 CEO Chase Carey told an investor meeting they still plan to extend the season beyond that. But it’s becoming increasingly clear they face opposition from within the sport.

The latest driver to voice concerns is Lewis Hamilton, who said he doesn’t expect to still be in F1 by the time four more races have been added.

“It already feels like we’re on race 25 this year to be honest so I don’t think it’s a good thing,” said Hamilton, who wants the calendar to be trimmed.

“I think 18 [races] was probably the best, back in the day. I’m someone that really loves racing but the season is long. It’s a long commitment for all of us. It’s a lot of time away from families. The season it getting longer and the off-time is getting shorter.”

As Hamilton alluded to, the strain is far greater for team staff than drivers. While the latter can arrive in time for media activity on Thursday and fly off shortly after the chequered flag on Sunday, the time commitment for engineers and mechanics is much greater.

Force India’s team principal Otmar Szafnauer explained the calendar has reached a point where if it gets any longer teams will have to incur a significant increase in staffing costs.

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“On average I’d say I’m gone four days for every grand prix weekend, maybe five,” he said. “But I’m in a privileged position where I can come late and leave early.

“The engineers do an extra two days.” Over a season, that means being away for 160 days, which Szafnauer says is “just not sustainable.”

For others the demand is greater still. “The mechanics do even more,” said Szafnauer “They’ll do seven days. I think our chief mechanic and team co-ordinator arrived on Monday here [in Brazil] and they’ll leave on Monday. So it’s a week.

“So if you say a week times 25, now it is half a year that you’re gone. I don’t think that’s sustainable.”

The calendar can’t grow much further before teams reach a tipping point where they have to hire many more employees. “If we get to 25 races then I can see double-staffing a lot of the roles.” Szafnauer believes.

That would mean a huge increase in costs at a time Liberty is trying to win teams over to the idea of a budget cap. How can it square that circle?

Its recent announcement of a new race in Vietnam gave an indication. The race will be held in April, around the same time as other Asian events. F1’s commercial managing director Sean Bratches said this is an example of how Liberty intends to “align our races by geography.”

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Grouping events in a similar region at the same time of year makes obvious sense from a logistical point of view, as less freight needs to be sent from Europe to Asia or the Americas. It’s not always a winner with race promoters, however, who have concerns over ticket sales from rival races in the same part of the world.

Re-ordering F1’s calendar to group races by region isn’t the work of a moment, as Bratches admits. “We are subject to some agreements we have inherited but ideally, and not necessarily in this order, we would like to have our races in the Asian and Australasian markets grouped, as we would the races in our American and European markets.”

This points towards a calendar which begins in Australasia, moves on to the European heartland, then heads to the Americas for the championship conclusion – which also happens to be at an ideal time for European viewers.

While the number of races will not increase next year, it is surely significant that the season starts a week earlier and finishes a week later.

This has created some breathing space and reduced the number of back-to-back races. But it’s surely only a matter of time until Liberty starts trying to plug those gaps.

The tricky question is going to be whether they can do it while also offering teams financial terms which allows them to absorb any increased staffing costs which may arise.

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2018 F1 season