I've read that it's thought those positives after a negative was due to a false negative in between the positives, possibly due to faulty test equipment or faulty administration of the test.

I believe that is why 2 negative test results are required before a patient is deemed to have recovered. Sounds like many of the tests aren't all that reliable.

I'm looking forward to the antibody tests, and easier to administer diagnostic tests, such as saliva testing, etc,. as we wait for a vaccine. Those nasal swab tests are really uncomfortable!

Time will tell if the vaccine will be good for more than one year at a time. I'd gladly have the vaccine annually, just like I'm happy to have a flu shot once a year.

There are ways to manipulate vaccines to get a balance between cellular and antibody response, or systemic and mucosal etc... If one type of response is more protective or one is more disease potentiating, developers can change up the balance in favor of what's more effective and safe. Will take longer!than 18 months, most likely if such is needed, as has been seen with RSV, or with FIP, a coronavirus disease in cats.

I don't believe there's conclusive evidence of re-infection, but there are people working on treatment options such as convalescent antibody therapy which could alleviate a lot of the threat. The antibodies don't last forever, but will last long enough to survive the illness, and perhaps long enough for us to develop a vaccine.

That some haven't been reinfected. It's a virus, mutates all the time, and will probably be with us for some time in various forms.

Hell the flu vaccine is only around 40% effective yet it helps save 10's of thousands of lives each year. Doesnt save everyone, though.

No idea; I've not heard anything about reinfection, except a Korean report without medical commentary. The I do know covid infection causes a person to generate antibodies, which should grant some level of immunity, but the level and duration are unknown.

Some people are building up the right proteins to provide future protection. Getting that protection to the masses should solve this damn problem. Not everyone will develop these proteins.