Southampton postal workers took impromptu industrial action in a dispute over working hours.
Ninety workers at Shirley Delivery Office walked out after colleague Chris Lawrie was suspended for allegedly not completing his deliveries.
Postal chaos was narrowly avoided after Communication Workers Union (CWU) bosses convinced the staff to return to their jobs after an hour.
Rob Hayhurst, area CWU rep, said the industrial action was the result of months of “bullying and harassment” over shift length.
He said: “Say for example you finish at 2pm but there’s lots of mail still to deliver, the procedure is that you call in and say you’ll bring it back for someone else to deliver. But recently we have been put under pressure and threatened with suspensions or docked pay to complete deliveries, even if we finish much later than we should.
“This deputy found himself in that situation and normally he would have worked on but on this day he couldn’t.
“He came in this morning to find himself suspended and so we took this action in response to that.”
Mr Lawrie, a postman who has worked at the Shirley office for 13 years, said he was suspended for “intentional delay of mail” but claims he worked his allotted hours and needed to finish on time to collect his children from school.
He said: “I followed my job to the letter. If a lorry blocks the road or if an old lady takes longer to answer the door because she is on a stair lift it adds time to your route and makes it more difficult to complete.
“My shift finished and I needed to pick up my kids but I was pressured and told if I cannot finish my route I would be suspended. What am I supposed to do?
“I feel let down by the procedures because we agreed to follow a process which management are not following.”
Mr Lawrie said his suspension was to be reviewed tomorrow.
A spokesman said “Royal Mail is disappointed at the unofficial action which took place this morning at Shirley delivery office. “We are pleased that colleagues have returned to work and we will focus on ensuring there is minimal impact on our service to customers. “We will now follow our normal conduct procedures for investigating the matter.”