A former coworker moved back to Aus (Perth?, he's Aussie) from British Columbia. He was awesome but apparently the timezone change was too large for him to cont

A former coworker moved back to Aus (Perth?, he's Aussie) from British Columbia. He was awesome but apparently the timezone change was too large for him to continue with the North American based org. Not sure the new work status. A friend-of-friend (U.S. nationality) might move to Sydney(?) for work with Amazon, to be closer to a team based there. Random data points and not direct answer but would assume large companies in general would be relevant here. Edit: I don't support amazon at all this is just for information transfer