This was my experience when I worked remotely for an East Coast company while based in SF. When I joined the company the expectation was that I would work Pacific hours, coming online around 9am PDT. Of course reality proved very different, and slowly my start time crept earlier and earlier until I found myself online at 6am daily - I was effectively working 3-4 hours longer than my East Coast colleagues simply because of the timezone I was located in. I didn't last long and moved to Bay Area company that allowed me to work from home 2-3 days a week.