Bakery chain Greggs has said its planned branch reopenings next week will now begin behind closed doors.
The sausage roll supplier is fearful of "the risk that excessive numbers of customers" may turn up.
Earlier this week, it announced plans to reopen 20 stores in the Newcastle area from Tuesday on a trial basis.
However, Greggs now says the reopenings will only be "to test our new operational safety measures" and it will not allow customers in.
Many fast food fans have been starved of their favourite food since the lockdown began in March, but Greggs had been one of a number of chains that revealed plans this week to begin a phased reopening.
Greggs has more than 2,050 shops across the country. All are currently closed, but the chain had decided to open 20 of them as part of a "controlled trial".
That trial will now be without customers, after the news struck a chord with fans.
A Greggs spokesperson said: "Due to significant interest in our 20-shop trial, and the risk that excessive numbers of customers may plan to visit Greggs, we will now initially operate these trials behind closed doors in order to effectively test our new operational safety measures.
"We will continue to review this and will invite walk-in customers into our shops only when we can be confident of doing so in the controlled manner we intended."
The chain refused to predict when the branches would be open to customers but indications are that it is keen to move to that phase as soon as possible.
That could mean doors opening to customers within days of the start of the two week 20-store trial.
If it does prove successful, Greggs hopes to open around 700 stores from 8 June.
It then hopes to reopen all stores by 1 July when the government's job retention scheme is due to end.
But that timing could change, depending on future government announcements.
Other fast food openings
Burger chain McDonald's reopened a branch this week but, like Greggs' revised plans, it is closed to customers and has only been opened up for "operational purposes".
The chain is "exploring social distancing measures for our crew, PPE options and opening in a limited capacity," it said.
"We will only reopen when we are absolutely confident we can have the right measures in place to ensure everyone's well-being," said Paul Pomroy, McDonald's UK and Ireland chief executive.
Fried chicken chain KFC has already reopened 20 restaurants for takeaway and delivery only and plans to open another 80 next week.
Nando's has reopened six of its UK restaurants for delivery. The peri-peri chicken chain has re-opened kitchens at four restaurants in London and two in Manchester.
Burger King and Pret A Manger have both opened some sites for delivery and takeaway in the past week.