TBF, the likes of B&Q, take-a-ways, and construction sites never had to close anyway, just operate with consideration to the social distancing rules.
Of course, they wouldn't be allowed to open otherwise. The thing is they did close though which they chose themselves (well, most of them closed). They're all now running out of patience which will just give this sense that the country is coming out of lockdown and this is just amplified by the likes of Wetherspoon twat talking about June.
It's going to be hard for the government to keep a lid on it. In that sense Johnson is right that he needs to give a longer date. The current 'not sure, can't say' approach is causing problems.