I know that Apple gets to choose which iOS version we are allowed to install on our devices. Currently you can install both 6.1.3 and 7.0. Does anyone know when Apple is likely to block 6.1.3 downgrades? I am currently testing 7.0 on my iPhone 4, but it's sluggishness is making me consider downgrading back to 6.1.3 for the time being. But when do I need to make the downgrade by?