The Rochestonian Captivity

Our usual priest-in-charge was absent through illness today, so a replacement vicar was called up.  The stand-in said it was good for him to be back home in Gillingham after exile in Rochester.  Would this posit that Rochester is Babylon (with all its connotations) and Gillingham is Zion?  That, were it not anachronistic, the cathedral city was a Mesopotamian Medway?  “By the river of Rochester/ Where we bowed down/ Yea-a, we wept/ When we remembered Gillingham.”