You omitted an important clause from your emphasis.
A requirement that guest workers return "to their home country after their period of work has concluded" hardly means they have to return home to renew.
If they renew their period of work would not be concluded.
Not clear to me that workers will be required to return home, the phase "There would be an opportunity for renewal." Doesn't make it clear renewal requires returning home." Could be, then again maybe not. I wait for a real plan to be presented, seems all we have so far is talking points. But I definately get the feeling Bush cares more about the illegal Mexican then Americans.