this is the latest os i found just now 5.0.0.966 for storm 2 9520
BlackBerry Handheld Software v5.0.0.966 (All Languages)
Package Version: 5.0.0.966
Consisting of:
Applications: 5.0.0.553
Software Platform: 4.2.0.264
File name: 9520_omanodrmjAllLang_PBr5.0.0_rel966_PL4.2.0.264_ A5.0.0.553_O2_UK.exe
File size: 148.03MB
this is the link
https://www.blackberry.com/Downloads...B73B97E1AAA491