The Tourism Authority of Thailand (TAT) said the Samui Plus scheme could be canceled if the current rate of infections doubles.
Meanwhile, officials have postponed the 7 + 7 island extension until the situation improves.
After a meeting with the Koh Samui office and Surat Thani province on Thursday, TAT Governor Yuthasak Supasorn said the reopening plan was still underway.
However, the Samui Plus model could be postponed or canceled if the infection rate grows twice the current number of 22 cases in a day or two, he added.
Mr. Yuthasak also stated that the island-hop plan for tourists after a seven-day stay in Phuket had been postponed over the recent spread of the virus.
Ratchaporn Poolsawadee, president of the Tourism Association of Koh Samui, said the island should prepare set up beds even though there are no severe Covid-19 cases to help with hospital caseloads.
Some hotels have become “hospitels” with over 200 beds for patients with mild symptoms.
But the Koh Samui Covid-19 center could implement stricter restrictions or revoke the entire opening plan if hospital cases reach 40 in two weeks, Mr. Ratchaporn added.
Samui Plus rules state that tourists must remain in the area’s quarantine facilities if there are more than 20 Covid-19 cases registered in hospitals over two weeks.
Meanwhile, the government announced that it would take stricter measures against companies that violate regulations.
Authorities also started investigating people who visited Speedy Lounge & Bar on Lamai Beach and Black Bamboo Club, as they are linked to a positive case.
Also, travelers in dark red and red zones must show negative Covid-19 test results issued no more than 72 hours before arriving, even if they are vaccinated.