The bakery chain has already begun a trial reopening across a number of its sites in the in the north-east of the country, following a pilot project in Newcastle's Tyneside area.
It now plans to reopen a further 800 of its sites by 18 June; with a final phase that would see Greggs' entire estate reopened due to be completed by July 1.
Greggs had previously set out a plan to have all 2,050 of the bakery chain’s UK branches open again by the beginning of July back in April.
However, it subsequently backtracked on those plans over fears that sites could become overcrowded with customers.
Now, though, CEO Roger Whiteside says the test stores have helped the chain work out its new operational safety measures, which will be rolled out on a wider scale when the time is right.
“The trials have been performing well, providing useful feedback from colleagues and customers, and we’ll continue to adapt as we learn more and work to the latest Government advice," he says.
“All shops will open with our new tested operational measures in place. And although they will open with a reduced range, this will be a significant step in us helping the nation get back up and running and serving the communities that we operate in.
“We’ll continue to look for the best ways to serve customers whilst keeping everyone safe, and as long as we can continue to do this, the final phase in our plan is to open all shops with our new operational measures in place by July 1."
Similarly to the majority UK operators across the sector, Greggs closed its entire estate back in late March as a result of the Coronavirus pandemic.