Apple is very likely to replace the old 8GB 3G model with a 8GB version of the new 3GS as soon as the one year old model becomes out of stock.
Someone at mobile phone operator Rogers sent two pictures of a webpage of the Canadian telco to mobile phone website BGR which refer to a document entitled "Rogers 8GB iPhone transitioning to 3GS".
The page points to the fact that Rogers will be coming up with a 8GB version of the 3GS fairly soon in order to complete a "smooth transition over to the new piece".
A 8GB iPhone 3GS - which costs $99 together with a monthly contract - is likely to be released towards the end of the year, and possibly in September as the back to school period kicks in and coincides with the end of life of the iPhone 3G worldwide.
Obviously a cheaper 3GS has a few implications. A 8GB 3GS version is cheaper to produce than the 8GB 3G and would be one less issue for networks and Apple to deal with as the supply chain is streamlined.
The 8GB 3GS would be similar to its bigger brothers and will only differ from them because of the onboard storage.
It also throws into disarray the plans of T-Mobile to provide the older generation iPhone 3G to its customers to prevent them from migrating to O2. The contract Apple has with the original mobile phone networks on which the iPhone was launch apparently covers new models only apparently. Leaving others such as T-Mobile to sell older versions. But if Apple no longer manufactures it, then it will be quite problematic.