The Info.plist is just a file, there's nothing you can modify or hook into directly to change its values after it's been loaded. I don't think an app's Info.plist is kept anywhere in nested array/dictionary form, and even if it is, most likely iOS will only read the value from there once and store it in a private property/ivar/whatever for quicker access. So if you want to modify an Info.plist setting at runtime, you'd probably need to find where its value is stored internally, and modify that.
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