The eagerly-awaited Android 4.0 upgrade that Sony promised for Xperia arc S, Xperia neo V and Xperia ray all 2011 Xperia phones now looks to be just around the bend. On its blog, Sony has announced that the first updates will start in mid-April for the Xperia Arc S, Xperia Neo V, and Xperia Ray, and will continue over the next four to six weeks. The second round, which will apply to the Xperia Arc, Xperia Play, Xperia Neo, Xperia Mini, Xperia Mini Pro, Xperia Pro, Xperia Active, and Sony Ericsson Live with Walkman, is more tentatively scheduled for the end of May or early June.

We've already seen betas for several of these devices, most recently the Xperia Play. This news, however, means that Xperia users won't need to unlock their phones or give up any features in order to get their hands on Ice Cream Sandwich. Sony says it'll be posting more information as the release date arrives, and that the update will only be available through PC Companion and Bridge for Mac — not as an over the air download. Sony also says it won't be notifying users when their update is ready, so that they'll make a "conscious and informed decision" to download it.

Update: As some readers have pointed out, Sony has started rolling out the Ice Cream Sandwich update to the first batch of phones (Xperia arc S, Xperia neo V and Xperia ray) in Sweden, Denmark, Iceland, Finland and Norway, with the updates making their way to Europe in the next "4-6 weeks."