Couldn't find on the linked article, but what's the lag for people who actually get tested? I mean, seems that this 3 years lag is because people only get test

Couldn't find on the linked article, but what's the lag for people who actually get tested? I mean, seems that this 3 years lag is because people only get tested if they have any apparent health issue and the doctor thinks it might be HIV. With Covid, it might take a few days for a test show positive, after exposure - say, Christmas dinner. If someone thinks they might have been exposed to HIV, how long until a test can safely tell it's a true negative/positive?