I would expect it to be on the order of weeks; I don't think there is much more to be added. There is a test branch for the patch that is being tested as updates and changes are made, so how much extra testing is required depends on the nature of any new fixes added (if such fixes are fairly safe and unlikely to affect anything else, then only basic tests need to be done again; more substantial changes, which may affect multiple systems, could require more thorough testing [though if it were to have too much of an impact on the release, it could get added in the next update, instead, if it wasn't a critical issue]).