The instructions for the rescue disk says that versions are changing all the time so you should create the USB or rescue disk right before you need it!!??
How in the world would I know when malware/viruses etc would hit me so I could make a disk or usb file just before time? I think making one is a great idea and I would like to make a usb file, but don’t you have a way of updating the rescue file on an ongoing basis?
Be aware that whilst you can boot up from the rescue CD, as far as I have been able to determine no one has actually been able to do so from a flash drive made from Avast 2014.