Electronics trade-in site Gazelle has today announced that it will lock trade-in prices for iPhones between now and September 9th for 50 days. This means that iPhone owners looking to upgrade can get a quote today, but not let go of their device until the new iPhone arrives, keeping the original quoted price.  Gazelle predicts that trade-in prices for iPhone 5s to fall up to 25% in the month following the expected iPhone 6 announcement.

Gazelle is also running another promotion in tandem, temporarily raising prices offered for iPhone 5s. Gazelle will now offer up to $350 for an iPhone 5s in perfect condition. Obviously, arranging an iPhone trade-in sooner rather than later will ensure you get the highest price for your devices.

Because of the deal, trade-in offers agreed on Gazelle’s website by September 9th can be frozen — meaning customers do not have to give away their phones until October 10th. See Gazelle’s website for more information and find out how much your device is worth.

Around the same time last year, Gazelle was offering about $350 for an iPhone 5, so the offered prices are comparable. However, as our comparison last year showed, it may be worth to look around as other traders may offer a better deal.