Apple is preparing to release its long-awaited white version of the iPhone 4, according to a new report. Citing three people with knowledge of the plans, Bloomberg reports that the handset will arrive for AT&T and Verizon Wireless in the next few weeks; one of the sources said it would arrive by the end of April. According to another of the sources, the release was stalled due to manufacturing challenges. After two prior delays, Apple announced in October 2010 that the white iPhone 4 would be delayed until this spring; Apple Senior Vice President of Worldwide Product Marketing Phil Schiller recently reiterated the spring 2011 timeframe for the device’s release.