Sony has been pretty good at keeping everyone informed about the Android 4.1 rollout for Xperia phones. But its performance in actually getting those updates out has been less impressive.The latest announcement from Sony is something of a mixed bag. The good news first, which is that the upgrade plans for the Xperia T, Xperia TX and Xperia V are 'progressing as planned'. Before you get too excited, that just means Jelly Bean will be sent out during February and March. Filter in some network tests and you can probably look at April as a date for that.Yes, that is the good news. If you have an Xperia P, Xperia J and Xperia Go, they are now down for the end of March, which will probably creep into May once the networks have given them a going over.That's not the latest set of updates to arrive though. The Xperia S, Xperia SL, Xperia Ion and Xperia Acro S will follow in the 'subsequent weeks'. Not even a date for that, so you can only imagine when it's likely to get through to users.Finally, Sony has confirmed that a decision has been taken 'not to upgrade' the Xperia U, Xperia Miro, Xperia Tipo, and Xperia Sola beyond Android 4.0. Presumably that's hardware-related - there's no other reason for an OS upgrade to be halted.With Key Lime Pie likely to be landing next year, that is something of a lengthy rollout. That OS is already said to be in testing, so it's unlikely to be long off. Possibly here before Sony gets round to upgrading to the current version of Android, which might be just a little embarrassing for the company.