Jim: no, I'm sorry, but you're simply wrong on this. As of the teaser in
"Voice," they knew that a world previously thought dead and uninhabited was in
fact sending out an *extremely* powerful beacon; that alone confirms the
existence of some new alien tech, probably very advanced. As soon as that
beacon was detected, and a report filed (which was almost immediate), the
Hyperion got its orders. Remember, Earth is obsessed with getting its hands
on new technology. The Hyperion continued to monitor reports as it proceeded
to B5. The Captain's line tracks.

Please don't describe things as "improbable" or "plot contrivances"
because you haven't thought them through. You do this frequently.

jms