T-Mobile USA have delayed the roll-out of the Android OS 1.5 Cupcake build to their US users, claiming the software update is still being "optimized". US-based forum members here at Android Community had flagged up the absence of any sign of Cupcake's arrival over the past week, despite the carrier's assertion that they would begin the launch at the end of last week.
Now T-Mobile USA are claiming that Cupcake still needs work "to ensure optimal functionality and smooth delivery". To that end, their roll-out schedule has been pushed back by "approximately a week", and their target complete date moved to early June (from the end of May). There is still no way to manually trigger the update, only wait until your T-Mobile G1 offers the new software to you.
The change in play prompts the question of what might differ between T-Mobile UK G1 handsets, which are already being updated, and the delayed USA version of Cupcake. Given that developers and UK customers are already using 1.5 it suggests that it's T-Mobile USA's own network which may be presenting a stumbling block to roll-out.
We’d like to provide an update on the rollout of Android 1.5 for T-Mobile G1 customers.
We are working diligently to get Android 1.5 out as soon as possible, while aiming to ensure a consistent, positive experience for our customers. We’re finalizing the build this week to ensure optimal functionality and smooth delivery. Therefore, the rollout schedule has been reset by approximately a week, and we expect all G1 customers will have the update by early June.
Your device will notify you when the update is available. Thank you for your patience and understanding." T-Mobile USA statement