The Prime Minister has announced that the road map easing earmarked for June 21 will be delayed for four weeks to July 19.
The announcement means that nightclubs will stay closed and people will be encouraged to keep up social distancing and working from home, although the 30-person limit on weddings will be lifted as planned.
“It’s a huge blow, both psychologically and financially," Gavin told the Yorkshire Evening Post.
"We’ve spent the last few weeks hiring team members and training them, getting ready for what we believed was the big day on Monday.
“As an industry, it’s going to have a devastating impact - it already has. Some nightclubs have gone forever and there’s thousands of others at risk now.
“A lot of businesses, which were very successful pre-pandemic, are disappearing because there’s little support.
“We’re always at the back of the queue."
There was a busy line-up of events planned at PRYZM from June 21, but Gavin said a contingency plan was in place.
Events will now be rescheduled and tickets refunded where requested, leaving the nightclub with little income for another four weeks.
Gavin added: "We’ve had furlough support, but now the worry is that landlords will want the rent paid - as the moratorium ends in June.
“And we’ll have to start contributing to furlough, when we’ve had minimal income. It’s an extra cost that, quite frankly, we could do without.
“Landlords have suffered, we’ve all suffered, and at the minute it’s just kicking the can further down the road.
“We all want to open, we all want to trade, so we need that longer term financial support.”
Gavin's fears have been reflected by Leeds nightclub Mint Warehouse, which has been forced to cancel its sold-out opening party on June 21.
As they released a statement backing the national #LetUsDance campaign, the team at Mint Warehouse said: "Hundreds of thousands of workers rely on our businesses, millions of customers rely on our businesses for their social wellbeing and access to culture.
"The Government has underestimated and undervalued the importance of these amazing industries. It must support these businesses financially and extend the current reliefs."
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