Ferd, not sure if you understood that correctly, so...

If you get a 1400 SC time, you can call scheduling and tell them that you are using your two hour commute, which means they will not be able to contact you during the first two hours of your SC, so in this case you don't actually have to be in SEA until 1600. But you will be expected to be able to report right away if they call you at 1600. I use it all the time...works great. Also, when you get two hours from the end of your short call, they will usually release you, if you call and use your sexy voice.