I've completed rescue procedure twice („if something's not right start from the beginning”), but got same problem twice. As I boot my disk as network device sda4 gets truncated to 461GB. Which is the original size of 500GB MyBook partition, but nowhere near 913GB I should get. When I repair the disk with usb2sata cable everything is OK, right partition size, right everything. Just after hooking it back again in the box it does get trimmed.
What should I do to get my full partition? („Start from beginning” is not what I'm hoping for.)