Almost 40% of initial bids on vehicles come ‘out-of-hours' - after 5pm and before 8am the next morning - says Cars Direct of its online auction operation. And some users have logged on to place a bid at 1am.

With the rise of unpaid overtime and the rise of out-of-hours emails more managers are effectively working an extra day every week and this research bears out that staff in dealerships are doing the same, it says.

Stats released by Ofcom show that over 90% of adults in the UK own a mobile-phone, with the average smart phone user checking their emails by 7.30am – while still in bed.

On top of this, Auto Trader said recently that two thirds of its site's traffic comes from smartphones or tablets.

Andy Brown, managing director of Cars Direct, said: "The research demonstrates how busy dealers are during the day as well as the convenience of the online format of our auctions, which means that bidders can reach us at all times of the day. Cars Direct have all the lots closing online at the same time, allowing buyers to place their bid at a time to suit them and then get on with the rest of their day.

"Trade buyers, like the rest of us, are busy people.

“They don't want or have the time to spend a whole day watching a physical auction either in the hall or online just waiting for the right car to come through and Cars Direct recognises this.”

Cars Direct’s website has been updated to be smart-phone and tablet compatible.

Cars Direct is a subsidiary of CD Auction Group.