I'd use "Sideslopes" for this, they automatically recompute. You'll have the full range of corridor instructions. Beware, a Sideslope only creates linework for material layer "Finish", but you can use other material layers for temporary elevation computations. They don't require an alignment, a normal linestring is enough.
It wouldn't be TBC if there wouldn't be a downside. The icon for a sidelope is extremely hard to see, especially in 3D view, a tiny little dot. 2D isn't much better.
And once a Sidelope is created the normal user can't change the start chainage of the Sideslope anymore. They only expose the end chainage in the properties pane, as "Station". Naming and description are misleading.
But with a macro they can be changed, hence my macro SCR_EditSidelope (https://github.com/RonnySchneider/SCR_Macros_Public - not compatible with 2026, still waiting for the license). That one allows you to change start, end chainage, template name and template spacing of existing Sideslopes. All things that TBC is hiding from you, don't ask me why. It also highlights the position of all sideslopes in the project, even on disabled layers, makes it easier to find the ridiculously tiny icons.