Which PHP 5.X version should be considered as Required

I have such question to supporters of older versions ..
Why you will need CI 4 to build applications for PHP 5.3 or PHP 5.4 Servers...
You can use easier CI 3 and thats it all..

I don't need to build applications for 5.3 or 5.4 servers now, but I may not be so lucky at my next job.

CI 2 will be unsupported in 6 months, how long will CI 3 be supported after CI 4 is released? Why would you support the use of an EOL framework when you are so opposed to supporting the use of a version of PHP which has reached EOL (5.3) or even one which is still supported (5.4), but which may reach EOL by the end of the development period for CI 4?

What features in 5.5 or 5.6 are going to make CI 4 so much better than it would be if it targets 5.4?

This is what I don't understand with people that want the framework to target 5.6 or PHP 7. Just because the framework supports PHP 5.4 doesn't mean you have to use it yourself.

Bonfire

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