Royal Mail workers have voted for just shy of three weeks of strike days over the course of October and November.
The industrial action, which is a wrangle over pay terms and working conditions, could have a huge impact on pre-Christmas shopping and other massive sales.
The strikes will come in the form of single days and also rolling action across Royal Mail Group’s network, the Communications Workers Union (CWU) has announced.
The CWU said the move revolves around the “outrageous” decision by senior management to withdraw from major national agreements, push ahead with cuts to workers’ terms and conditions, and a “complete side-lining” of the union.
Royal Mail strike dates
Organisers at CWU said there will be 19 days of strike action over the course of the next two months.
While the exact dates have not been announced, union officials said the walkouts will cover peak mail periods such as Black Friday, Cyber Monday and the lead-up to Christmas.
Black Friday is on Friday, November 25.
The day, originally an American invention coinciding with the first Friday after Thanksgiving, is often a 24-hour period when online retail websites, including Amazon, slash their prices to entice those with disposable cash.
Cyber Monday will then take place only a few days later, on November 28.
Also related to the Thanksgiving holiday season in the US, Stateside it has become the second biggest shopping day of the year.
Will deliveries be delayed during the Royal Mail strikes?
Hundreds - if not thousands - of postal workers, including those delivering and sorting post and parcels, are likely to form picket lines on the strike days.
It means home and business deliveries will almost certainly be delayed.
The CWU is expected to announce more information on its chosen dates, beyond those coinciding with Black Friday and Cyber Monday, in the coming weeks.
Royal Mail has recognised the strikes are likely to cause "inconvenience" for customers.
"We are doing all we can to minimise any delays and keep people, businesses and the country connected," a spokesman said.
What are the Royal Mail strikes about?
CWU and the Royal Mail were involved in pay talks, but a row has blown up over the firm’s handling of the negotiations.
Royal Mail was sold off by the Conservative government in 2014, meaning it operates as a private venture.
The company says it is making heavy losses on a daily basis, with changes to how it operates needed in order to keep it going.
CWU general secretary Dave Ward said: “This is a significant announcement, but it is one which matches the level of anger our members feel at the way Royal Mail Group has treated them.
“The chief executive of Royal Mail Group is treating postal workers as if they are stupid.
“These are the same people that have kept the country connected and returned Royal Mail Group to record profit.
“Postal workers across the UK now face the fight of their lives to save their jobs and the service they provide to every household and business in the UK."
A Royal Mail spokesperson, in a statement on Tuesday (September 27), said: “Royal Mail is losing £1million a day and must change faster in response to changing customer demands. We operate in a competitive market, and our customers have choices.
“Further strikes and resistance to transformation by CWU will only make our financial position worse, and threatens the long-term job security of our postmen and women.
“The CWU has a responsibility to recognise the reality of the situation Royal Mail faces as a business and engage urgently on the changes required."
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