GP68 - later model - dedicated RSS vs CP50 RSS

[g8tzl2004]

I have a Hong Kong GP68 which I guess is a later model.

The GP68 is 1.5KHz off freq so I want to use the RSS to correctly align the radio. I'm aware that the RSS is ONLY for alignment NOT programming.

I had assumed that the RSS for the CP50 could be used. I have RVN4159A and the RSS Help Pages state that the RSS will program both the CP50 and GP68.

However , when I try and Read or go into Service Mode, I'm getting a Serial Bus Error - Accessing Serial Bus..etc

I researched the archives again and found a very brief mention that the later version of the GP68 requires its own RSS rather than the CP50 RSS.

Just checking this is the case. If so, does anybody know the RVN number and latest version number?

Thanks