Ok, you’re not going to be happy about this one.

According to AndroidCentral, wireless carrier AT&T has quietly raised early and exception upgrade pricing for iPhones and other smartphones. A notice to store staff has warned that, as of Sunday, users are paying US$50 more. The move would change the premature upgrade price from US$249 for an iPhone 3GS to US$299, and up to US$449 or US$549 for an iPhone 4 before normal eligibility comes up.

A separate memo both confirms the price hikes and showed across-the-board pricing increases. With the exception of the iPhone, pricing will go up sharply for anyone buying a phone contract-free or a shortened one-year contract. Those without a contract will pay at least US$50 more, AndroidCentral saw, while one-year buyers will spend US$150 more.

Basic messaging phones are also going up by US$20 off-contract or US$10 on a one-year deal.

AT&T has yet to officially confirm the rate hikes, though they will ultimately have the largest impact on non-Apple hardware. Pricing for Android, BlackBerry, and Windows Phone 7 devices will now mostly be competitive on a two-year plan where the iPhone may be the more reasonable deal on shortened terms.

Stay tuned for additional details as they become available