MARBLEHEAD – Stay tuned.That’s the advice of Public Health Director Wayne Attridge today as he prepares for Saturday’s H1N1 Flu Clinic – the clinic will be Marblehead’s first and it also might be Marblehead’s last.And the rules for “swine flu” vaccinations keep changing day by day.Attridge told selectmen Wednesday night that the clinic will be Saturday from 10 a.m.-1 p.m. at the Marblehead Community Center on Humphrey Street. According to a flyer he gave reporters that evening it was for anyone 5-24 years of age, household contacts of infants under 6 months and pregnant women in the third trimester (seven-nine months) and healthcare workers who have direct patient contact. Parents who need a second shot for a child under 10 are asked to bring documentation showing the date of the child’s first shot.But that has now changed.According to a “news flash” on the Board of Health page of the Marblehead Web site, the clinic has now been opened to a wider population.It is open to residents 5-18 years of age and 2-4 years of age, if they are completely healthy and qualify for H1N1 Nasal Spray vaccine. It is also open to residents 19 to 64 years of age who have chronic health conditions.It will still be open to household contacts of pregnant women and infants under 6 months of age, and healthcare workers. Documentation showing the date of the first dose is still required for children 5-10 years of age who need a second dose.Further information – and any possible further changes – will be available on the health board page of the Marblehead Web site (www.marblehead.org) or at the health office, 781-631-0212.”The DPH (Massachusetts Department of Public Health) has not been consistent,” Attridge said Thursday, explaining that he found the changes posted on the DPH Web site Thursday, with no announcement.”It’s so frustrating. Our staff has been doing yeoman work but we take a lot of grief because of these changes and the way the changes come down.””We want to get this vaccine out to people but we have to show some sort of organization and make sure we have enough for everyone who shows up.”Attridge said he knew of a doctor’s office that currently has a surplus of H1N1 vaccine. He credited the Cape Ann Community Health Network with helping the town stay on top of the situation.Attridge predicted that the town will have another seasonal flu vaccine clinic after Jan. 1. He declined to predict when the town will have its next “swine flu” clinic because the vaccine appears to be in short supply at the moment and he isn’t sure what the future holds.”We may have a second clinic,” Attridge said. “I’m not going to predict it because we don’t know.”