What we need is something that favours both sides - whilst just cancelling TRSS would be great, the company would want us to not leave in return. Having a an increasing bond to cover the extra pay would be impossible to enforce, or claim against (and noone would want to sign up to another bond), so why not...
... at the end of the TRSS period (5 yrs), pay us back 50% of the money we paid to eJ. That would encourage us to stay, and we could now "think" that we were in effect on the full ('B' scale) salary (assuming most are roughly half way through the scheme) for the latter part of the TRSS sentence.