File photo of Apple's iPhone 5S being displayed at an Apple shop in Tokyo's Ginza shopping district
Apple's new iPhone 5S is displayed at an Apple shop in Tokyo's Ginza shopping district in this September 20, 2013 file photo. REUTERS/Yuya Shino/Files

What is the best indicator that the iPhone 6 release date is fast approaching? Loads of iPhone 5S deals that leave Apple's 2013 flagship very hard to resist.

Apple has earlier announced that starting on May 8, iPhone owners will be able to upgrade to the iPhone 5S or 5C by swapping their old units in exchange for significant price cuts on a fresh purchase. This big push, according to CNET, is seen as preparatory move for the tech giant's iPhone 6 thrust this 2014.

However, U.S. retailer Target is attempting to pre-empt the supposed in-house Apple iPhone deals with its combo of trade in and gadget discount deals that according to BGR will allow buyers to take their choice of iPhones with or without service contracts.

Up for grabs are the iPhone 5S and iPhone 5C in 16GB configuration.

For those wanting to cash in on their present, preferably in shiny and perfect working condition, up to $300 worth of gift cards await them, which in turn can be used to shave off the standard sticker price of off-contract 5S and 5C.

Target sells the devices at $700 and $600 respectively but with the maximum value of the gift cards that the retailer dangles, iPhone shoppers will be able to take home the 5S and 5C for only $400 and $300.

It should be noted, however, that securing the highest gift card value will largely depend on the iPhone models (plus its actual state upon inspection) that consumers are willing to turn in. It can be assumed that a fresh-looking iPhone 5, meaning no nicks and scruffs and the body seems just right out of the box, will merit the highest appraisal possible.

The deal, which runs from May 4 to 10, is available on Target's physical and online stores and the company dutifully reminds that on top of the already alluring gadget exchange deal, a five per cent on the spot discount is available for Target REDcard holders, leaving the iPhone 5S for the taking at only $380.

Now when tied up with 2-year service agreement from major U.S. telcos, the iPhone 5S and 5C on Target is undeniably a lure for bargain hunters. Both coming with 16GB internal memory, the devices sit on the shelf marked only $120 and $30 respectively.

But it is the 5S that promises more savings as Target is willing to slap the outgoing flagship with another $20 price cut, thanks to an accompanying Target Gift Card that is exclusive for buyers opting for the metallic handset instead of the colourful yet plastic-wrapped 5C.

This emphasis on clearing out the iPhone 5S inventory both from Apple and its retail and distributing partners like Target seems to reinforce the notion that revelation for its sequel, the iPhone 6, is happening very soon.

Analysts though are looking to September 2014 as the earliest release date of the iPhone 6, which is for the 4.7-inch model while the 5.5-inch edition or the first iPhone phablet is set for unveiling in December.