Black Friday started earlier this year as shoppers turned to online services during the pandemic.

The number of parcels being delivered started increasing sharply from the end of October.

By last week, it had already surpassed last year’s post-Black Friday peak, according to new data.

But some retailers are worried there will be delays in customers receiving their orders because of stock shortages and overwhelming levels of demand.

Metapack, which acts as a go-between for retailers and couriers, said parcel volumes were already up by 70% this week, compared with the same week last year.

“I’m sure we’re having a very digital Christmas because people can’t shop offline,” said Bruce Fair, the company’s chief revenue officer.

In a normal year, retailers would expect the week in which Black Friday falls to be the most profitable of the year. But sales were already up by between 50 and 60% in each of the first three weeks of November, according to IMRG, which collects data from online retailing companies.

“That’s among the strongest growth that we’ve seen all year… those are very very big figures leading into this week,” said Andy Mulcahy, strategy and insight director at the organisation.

By 09:00 on Friday, Metapack was working with retailers to deliver between 2 and 2.5 million orders, but Mr Fair says the biggest day of the year for despatching orders will come next week.

“The retailers will take all of their orders today, on Saturday and on Sunday, and then most of the despatch against those orders will happen on Monday next week”, he predicted.

And he thinks in order to cope with the volume of orders, retailers will start giving shoppers a later delivery date.

“Standard delivery is three to five days but they’ll stretch that out, so standard delivery is now seven to 10 days in order to avoid consumer disappointment”.

Problems in the global supply chain, due to the pandemic, mean some companies are struggling to get hold of new stock so that they can fulfil their orders.

image caption“We will not let anyone down”, says Gavin Ucko, despite difficulties in getting hold of stock

“It’s our very best products that we’re waiting for at the moment. The things which sell so quickly”, Gavin Ucko, managing director of the Happy Puzzle Company told the BBC.

Mr Ucko is waiting for around 60,000 puzzles and games in four containers to arrive in his warehouse from China.

“If we don’t have those goods on time that’s going to represent an enormous problem for us, because we’re going to be stuck with stock at the other end of Christmas. And this is stock which is being brought in to sell pre-Christmas.”

Mr Ucko says he is determined to get orders out to customers, even if means upgrading them to next-day delivery at the company’s expense.

Other firms, however, have faced criticism from consumers for not offering premium delivery services during the Black Friday sales event.

Several customers of Asos, the online fashion store, complained on Twitter that they were not being offered next-day delivery, even though they had already paid for it via an annual online subscription.

Some asked whether they would be receiving a discount due to the lack of service.

Asos told the BBC that during “peaking ordering periods”, such as Black Friday, delivery times may be extended.

Delivery firms have recently been on big recruitment drives in order to cope with the extra demand created by this year’s lockdowns.

Hermes, for example, said in July it would create 10,500 jobs in the UK after seeing a surge in demand from people shopping from home.

DPD also announced plans to recruit 3,500 drivers and 2,500 support staff, including mechanics and parcel sorters.

Its boss Dwain McDonald described the lockdown period as the “biggest boom in online retailing” the UK had ever seen.