An analyst claimed that iPad 5 and iPhone 5 with plastic casing were scheduled for launch in early September, while the full-fledged iPhone 5S release date was pushed back to the end of the month.

According to the latest note of KGI Securities analyst Ming-Chi Kuo, the rumoured iPhone 5S was facing production delays and setbacks with the inclusion of various components. Thus, it could yield to a limited supply upon release date.

Kuo said that the next iPhone's supply may be similar to the iPhone 5. "While shipments forecasts may still grow sharply in 4Q13, we are concerned iPhone 5S may face the same problem as its predecessor, namely that by the time supply matures, demand will already have waned, hurting shipments, " Kuo wrote in his note as cited by AppleInsider.

The analyst also stated that the iPhone 5 with plastic casing and iPad 5 will be released earlier than iPhone 5S. Kuo speculated that the iPhone model will bear a tag price of $450 to $550.

iPad 5 could be the highlight of the range, as no successor of iPad Mini will be released this year. The delay could be due to the production of the Retina display and the components required to improve the power efficiency needed in a smaller tablet, Apple will likely shoot for a launch in March or April 2014.

Kuo has a good reputation when it comes to Apple-related rumours.

We can deduce that instead of iPad Mini 2 debuting alongside the next generation of iPad 5, Apple will introduce the plastic version of iPhone 5 in September. It also served as clue that the low-cost iPhone may boast the specs and features of iPhone 5.

The iPad 5, on the other hand, was rumoured to have slimmer bezels while still sporting the same sleek and sophisticated design.

But we should still treat these rumours with a grain of salt until Apple officially hands invitations anytime soon.