There probably is a CID53 for the W580i, but whether your phone is subject for the upgrade probably depends entirely on what branding you have on your phone. I updated my K800i to CID53 yesterday, and I'm pretty frustrated because I found that I am now unable to mod my phone anymore due to the new restrictions put in place, so if you're a phone modder, stay well clear of CID53 - it's one of Sony's death traps. If you do not intend to mod your phone however, a CID53 upgrade would do no harm I suppose. I know you're saying that your phone does not seem to want to upgrade to CID53, but to be honest, you're not missing out on much. I have noticed no difference whatsoever in terms of performance from the phone (except my lovely modded icons have been removed
).