You must upgrade existing Relay Servers and RSOEs, when you upgrade Unwired Platform to version 2.0.
Upgrading Relay Server with an Archive
Find the relay server archive on the Unwired Platform installation media. This archive upgrades relay server binaries when you extract content on the relay server host.
Upgrading RSOE and Migrating Configuration Files
As of this release, configuring RSOE with the relayserver.properties file is no longer supported, nor is the RSOE installed to run as a separate service. Now, RSOE runs as a separate process with Unwired Server service. Consequently, you must migrate this file and upgrade RSOE on each Unwired Server node in your environment.