Hi @tgeoghegan
First of all, let me welcome you to the community! Feel free to Introduce yourself 
to everyone if you want to 
Material update in ETABS is currently not supported by design. This is to to ensure Structural engineers won’t have unwanted changes in their setup (materials, profiles) coming from other applications. When a material is received, we check if a material with the same name is present and if so, we just use that.
Could you tell me more about your workflow? Sections can change after running the analysis in ETABS so I was wondering where you usually manage material and section properties.