I have a well worn copy of Programming Flex 2. An excellent guide to programming Flex without the need to adopt Flex/FlashBuilder.
Do you intend to publish "Programming Flex 4.5"
sorry for the delay in responding to you. I'm not sure if an update is in the works for the Programming Flex book, but perhaps one of our editors would chime in about that.
We do have some available now on the topic, and the list is here:
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