E.memoryArea not working on ESP8266 (due to char-iterator ?)

Flash in ESP8266 is mirrored (windowed?) to 0x40200000.
So if you want to use E.memoryArea for 1011712 (0xf7000) please check 0x0402f7000.
BTW, you could check for free flash, since value given by esp8266.getFreeFlash() returns a value which is designed to be free. If firmware does not use all of reserved memory for firmware, there is some more available flash, right now starting at 0x72000(0x40272000)
One more BTW, for more confusion, flash.read does adress calculation internally.

flash = require("Flash");
function mem(){
  for(var i = 0x70000;i < 0x80000;i+=4096){
    console.log(i.toString(16),flash.read(8,i));
  }
}

if this returns 255 for all fields, usually this is available flash