Nope, it is not a simple matter. Lots of lighterage and cartage operations going on to move oil out of the tanker into other refineries.
British Laurel for example:
2012 April 23rd, 00:01:06 UTC Benicia Anchorage
2012 April 21st, 15:00:15 UTC Benicia
2012 April 18th, 13:30:06 UTC El Segundo
2012 February 28th, 18:00:01 UTC Balboa Panama
2012 February 16th, 15:00:01 UTC Long Beach
2012 January 29th, 07:00:34 UTC Uswc Lighterage
2012 January 27th, 01:00:02 UTC Long Beach
2012 January 25th, 03:00:01 UTC Uswc Lighterage
2012 January 21st, 20:00:13 UTC Long Beach
2012 January 16th, 18:00:20 UTC Uswc Lighterage
going to Benicia, Long Beach etc. numerous times to off load oil.