A tourism expert whose family owned a string of venues on the north coast has warned the Northern Ireland industry risks "handing over its silver" by reopening hotels three weeks after the Republic.
Hotels and other accommodation here are due to open on July 20.
The date was chosen to coordinate with the Republic. However, last week Taoiseach Leo Varadkar fast-forwarded his country's lockdown exit plan by announcing that hotels, restaurants and bars serving food could open on June 29.
It has prompted calls for Northern Ireland to move at a faster pace.
Lyn Fawcett said a three-week gap was akin to handing the Republic an open goal.
With the Executive under pressure to move more quickly, the issue is high on the agenda when it meets tomorrow.
First Minister Arlene Foster has said she "very much" hopes the date for hotels to reopen could be brought forward.
Health Minister Robin Swann said there were "strategic and creative ways" in which the hospitality sector could reopen, including using outdoor space where the virus was less likely to spread.
He said reopening had to be done "in a managed, respectful, measured approach so that it doesn't help the spread of the virus".
But Mr Fawcett, whose family owned Northern Counties, Fawcetts Royal and The Lismara Hotels in Portrush and The Strand Hotel in Portstewart, said Northern Ireland would lose three key weeks of holiday business to the Republic if it waits until July 20.
The former Ulster University hospitality and tourism lecturer, who owns self-catering cottages on the Causeway Coast, said there was pent-up demand among people for a holiday.
"I expect that people are so cabin-crazy that first opportunity they have, they will go somewhere. Those three weeks up until July 20 will capture a very large proportion of the money that would be spent in NI.
"I've written to my MP Sammy Wilson to say 'you really need to keep an eye on this'," he said.
"Otherwise, you're giving the Republic our silver and allowing them to eat our lunch off it too.
"Basically the summer season is about eight to 10 weeks... As it stands, we're losing about 30% of that season and you can't recapture that.
"I'm not suggesting we should blindly follow the Republic as they have different statistics to us but Stormont needs to look at the figures on a daily basis and revise their opening dates accordingly.
"It's too much of an open goal to allow a holiday location in a country so close to us to get all our holiday spending."
Mr Fawcett said that if he is unable to open his holiday cottages before July 20, he will have lost 50% of a year's typical turnover.
He said key holiday dates have already been lost, adding: "Portrush usually does very well at Easter, and the North West 200; the Portrush Raft Race does a lot of business.
"And with the double-May bank holiday, including the VE Day holiday on May 8, that would have been a significant amount of business, and that's all lost."
He said the loss of the Airwaves Portrush Airshow, which usually takes place at the end of August but has been cancelled this year due to a lack of council funding, would not be a major deterrent to tourists.
In addition, he said the absence of amusement park Barry's, which is on the market and is not expected to be open during the summer, was also unlikely to detract from the draw of the north coast to holidaymakers.
"We have tremendous strength in terms of our beaches, the local environment, the harbour, all those things are beautiful and unspoilt.
"We have a cluster of amazing restaurants like the Ramore Complex, Bushmills Inn, Amici in Portstewart - it really is a cultural delight for food.
"The owners of Barry's have made a fantastic contribution to Portrush and I gather they're doing their best to ensure it continues as a going concern and that I believe to be their wish and desire, as it would be for all of us."
Mr Fawcett said he believed people would embrace staycations but would shy away from air travel in the short-term.
He added: "I think it will take people a while to get the confidence to travel by air. Some people will wait and see just how safe it is to travel by air on international and continental holidays. I don't think it will make a dramatic difference to people's propensity to travel internationally in the long-term but people will look at staycations in the short-term."
Mr Fawcett said the summer season could be extended into September and October as people aim to get their usual allotment of breaks, but added: "Northern Ireland just doesn't have the capacity to take everyone who wants a staycation during the last week in July into August.
"I think the window of breaks will extend into autumn. In my cottages, I would say September and October this year are looking slightly stronger than they were this time last year."
He urged the Executive to reopen the accommodation sector in phases, as it has with the retail sector.
"They need to consider phasing in different types of accommodation, like caravan parks, self-catering accommodation, as they're all very capable of very high levels of social-distancing."