hali hazirda jb'li olanlarin gecmesi gerekmiyor, serverlarin ne oldugunun onemi kalmiyor. host dosyasinda ufak bir degisiklik yetiyor. cydia'yi actiginizda tepede shsh yazar oradan sonra hangi surumler icin shsh dosyaniz oldugunu gorebilirsiniz.
"When you open Cydia, it automatically saves your device's available SHSH (signatures), so that you can use Cydia's signature server replacement to restore your device with those firmware versions later (after Apple no longer signs them).
Note: Access to saving SHSH is entirely based on Apple's servers and is not affected by your device's current version (or other properties). This means that Cydia can only save SHSH for firmwares being signed by Apple at the moment when you open Cydia, and after Apple releases a new firmware, Cydia has no way to save SHSH for any previous version, even if it's currently running on your device."
cydia.saurik.com