The specification of the whisper node says that it has a 4MBit SPI flash but I couldn't find any instructions on how to access that. Could anyone guide me on how I can use that memory?

Also, in the documentation, it says that the whisper node has a bootloader that is capable to do remote firmware update over air but the link to the documentation about the bootloader does not work. So how exactly do we do remote update? Are there any instructions anywhere else?