Jaguar Land Rover (JLR) is set to restart some production this week following a major cyber-attack that forced the carmaker to shut down factories and send workers home.

Manufacturing will resume first at JLR’s engine factory in Wolverhampton, but it is expected to be several weeks before all operations are running at full capacity, with other sites to return gradually.

Work at JLR’s three UK sites in the West Midlands and Merseyside has been suspended since a cyber-attack at the end of August forced the company to shut down.

The resumption of operations will be a welcome relief to JLR’s array of suppliers, some of which are small businesses that have faced huge financial pressure.

JLR is continuing to investigate the attack, which forced the company to shut its IT systems and send workers home.

That safety measure paralysed virtually every aspect of JLR’s business and meant it could not build or sell any cars, or distribute parts to service centres.

As well as its UK sites in Solihull, Halewood and Wolverhampton, the carmaker’s factories in Slovakia, China and India have also been affected by the shutdown.

The hack is believed to be costing the company at least £50m a week in lost production. A group calling itself Scattered Lapsus$ Hunters has claimed responsibility.

About 30,000 people are directly employed at the company’s plants with about 200,000 working for firms in the supply chain. Some of these firms supply parts exclusively to JLR, while others sell components to other carmakers as well.

Evtec Group is a so-called “tier one” supplier which provides parts directly to JLR, while sourcing the materials it needs from other companies lower down the supply chain.

It has 1,250 employees mostly based in the West Midlands, but much like JLR’s factories, its main plants in Coventry and Kidderminster have been at a virtual standstill for weeks.

Machines have been shut down, parts set to be shipped out piled high and most staff sent home on 80% of their usual pay.

Workers will return in the next few years, but Evtec’s chairman David Roberts told the BBC the stoppage has had a dramatic impact on communities in the West Midlands, and uncertainty remains.

“It has had a really detrimental effect, it’s devastating. There’s a lot of vulnerable people out there who are now really concerned – the cost of living, Christmas coming up, when will they return to work in earnest?”

Engineer Ben Brindley said the length of the disruption has fuelled fears about his job.

“There’s only so much refurbishment or decorating you can do whilst you’re at home,” he said.

“The longer it goes on for, the more worried you get really. You start to think – will I have a job to come back to?”

Experts have warned while production will gradually resume, the impact of the cyber-attack on JLR is not over.

The company said its recovery programme was “firmly under way” and that its global parts logistics centre, which supplies spare parts to dealerships for vehicle servicing, was “returning to full operations”.

But when it comes to restarting carmaking, experts point out the process is not like flicking a switch. Some industrial processes can take days to get back up and running, while JLR has already said the restart will be done in phases.

Secondly, suppliers that have lost income during the shutdown may not be able to bounce back as quickly.

Andy Palmer, who has held senior roles at Nissan and was the former boss of Aston Martin, said the restart process would “take a while”, and added the supply chain was “broken and needs to be repaired”.

“The other issue is the impact on suppliers. Some of them… might not make it, and if any of those fail then that’s more disruption in the supply chain,” he said.

While the government has agreed to back loans for JLR to support suppliers, Evtec’s Mr Roberts said the policy was a “toothless solution”.

“It doesn’t help the UK’s advanced manufacturing sector one iota, because we don’t see any of those funds,” he said.

“We asked the government directly, at ministerial level, to directly support the sector. They listened, but they did nothing. It’s almost like they’ve turned a deaf ear to the needs of advanced manufacturing, which is a key platform of the Industrial Strategy”.

He said the government needed to support labour and payroll costs and provide tax reliefs for a period of time while firms recover.

“Production will begin, but it’s too late. All of our companies have had six weeks of zero sales and still had to pay their costs,” Mr Roberts said.

The government has said it is in “daily contact with JLR and cyber experts to listen to concerns and what support can be provided to get production back online.”