Which is exactly why the protocol is: 1. Your phone transmits a temporary random number. 2. Your phone stores, but never uploads, list of all the numbers it ha

Which is exactly why the protocol is: 1. Your phone transmits a temporary random number. 2. Your phone stores, but never uploads, list of all the numbers it has seen for a prolonged period. 3. Your phone downloads daily a list of published numbers and cross-references that with the local list. Literally the only time you upload anything is when you report being positive.