Holacracy Community of Practice Archive, 2015-2019 Community Holacracy Web Site

I pondered your question and reviewed the constitution and here is one more option which takes the direction of bringing it up as a tension within the circle.

2.2.3 Amending the Lead Link Role

A Circle may not add Accountabilities or other functions to its own Lead Link Role, or modify the Role’s Purpose, or remove the Role entirely.

However, a Circle may remove any Accountabilities, Domains, authorities, or functions of its Lead Link Role, either by placing them on another Role within the Circle, or by defining an alternate means of enacting them. When this occurs, it automatically removes the relevant element or authority from the Lead Link Role, for as long as the delegation remains in place.
If I am not mistaken, this can occur within your circle so at a governance meeting, someone can propose New Roles which holds the acquired accountabilities and have Lead Link to fill those new roles with members who have more competence with those accountabilities. 
I am curious what other coaches think about that idea.