The purported September release date of the iPhone 5S and the low-cost iPhone Lite could suffer a minor setback, as Apple deals with a fresh management turmoil that involves a key company executive.

Over the weekend, MacRumors reported that the biography of Bob Mansfield, Apple's senior vice president for technology, was mysteriously removed from the company's official site, sparking rumours of a redux of the same problem that transpired in late 2012.

Recall that in the aftermath of the bungled iOS Map that was launched with the iPhone 5, October last year, long-time Apple executive Scott Forstall, also reportedly a Steve Jobs protégé, was forced out of the tech firm as part of Apple's corrective measures.

Prior to that, Mr Mansfield had already indicated that he was leaving Apple, but Tim Cook, the company CEO, lured him back following Mr Forstall's departure, supposedly to quell the snowballing management disturbance that started when Mr Mansfield voiced out his retirement plans last June 2012.

Apparently, the insurrection worsened with Mr Forstall's exit, though it died down when Mr Mansfield decided to stay with Apple at least until 2014. A handsome pay of $2 million per month convinced the former to postpone his retirement, according to AppleInsider.

Now it appeared that Mr Mansfield is no longer part of Apple's executive roll, which was confirmed in a tweet by Reuters reporter Poornima Gupta.

"Bob (Mansfield) is no longer going to be on Apple's executive team," Apple told AllThingsD.

His expertise, however, will remain under the employ of the tech giant, as the same report also claimed that Mr Mansfield will handle special projects and will be reporting directly to Mr Cook for such undertakings.

The new development seemed to add up glitches on the already rough months leading to Apple's planned release dates for the iPhone 5S and the iPhone Lite, productions of which, according to analysts, are still facing serious challenges that could lead to delays.

Should Apple's 2013 business calendar remain in place, the cheaper iPhone would be issued by early September, while the iPhone 5S is set for a late September or early October launch.