Less than 24 hours after Sprint first provided an update on the availability of its version of the Samsung Galaxy S III, the carrier has shed some more light on the situation. Sprint now says that, "due to overwhelming demand for Galaxy S® III worldwide," Samsung has said that it won't be able to deliver enough inventory for Sprint to actually start selling it on June 21. Originally Sprint said that it would have the Galaxy S III for sale online and through telesales on the June 21, but it seems that that's no longer the case. While Sprint didn't say when it might be able to launch the Galaxy S III, it did say that it's working with Samsung to get a schedule together that'll support a Sprint launch.

On the pre-order front, Sprint says that it's begun shipping the 16GB Galaxy S III to customers that participated in the pre-sale and that deliveries are expected to happen on June 21. The carrier says that it "hopes" to begin shipping pre-orders of the 32GB model next week.

Finally, it appears that pre-orders of the AT&T Galaxy S III may be arriving a little later than previously expected. At first we heard that orders were expected to begin shipping on June 18, then that date was apparently bumped back to June 21, and now Android Central says that the new arrival date for pre-orders is "on or before June 28."

It's also worth noting that a leak yesterday claimed that T-Mobile doesn't anticipate that it'll have enough Galaxy S III inventory for a full-on June 21 launch like it had originally planned. Instead, the carrier is said to be splitting the release into two phases, with the T-Mobile website and stores in the top 29 markets receiving units on June 21 and other channels getting the devices next week. Overall it's starting to look like the Galaxy S III could be kind of tough to come by for folks that wanted one this week. If you're one of the folks whose Galaxy S III launch plans have been affected by by this "overwhelming demand," why not check out Aaron's reviews of the Sprint and AT&T models to help to pass the time until you get your device? They're both embedded below for your viewing pleasure.

Via Sprint, Android Central