HopRocket (hopback) questions: "captive" wort and effect at beginning vs. end of run

Brewed a double IPA last Sunday and used a HopRocket as a hopback for the first time (standard setup: kettle -> HopRocket -> counterflow chiller -> fermenter using gravity feed.) Overall very pleased with the device. Seemed to add a hop character that was quite different than hops in the kettle or dry hopping. We brew 10G batches and split the output from the kettle into 2 carboys. First half of the "drain" goes into one carboy, last into the second.

I'm interested in knowing if anyone has done any testing on the effects of a hopback at the beginning vs. end of the run. Will there be noticeable differences between the carboys? We thought about swapping the output hose more frequently to try and even out any differences, but that seemed like too much work. For those of you that use a hopback and split the output, how do you handle this?

Also the HopRocket "captured" about 5 cups of wort. Is there any way other than a pump to get this wort to drain through the chiller? Seemed a shame to waste that so we froze it and may use it for priming.