Looks like that's an antibody-only test, which is 3rd generation, but hard to tell. Your 8-week result is unlikely to change. The recommended time to consider a result conclusive with a 3rd generation test is 90 days. It is up to you whether you consider 11 weeks to be good enough or not.
The website states 99.8% accuracy, which is as accurate as any test on the market for any disease. I have already posted my opinion on the likelihood that it will change. Kindly read my first response.