On App Hosting, yes. Automatic vertical scaling increases and decreases container resources with demand, within the baseline and ceiling you configure. Reserved resources remain part of your baseline; burst usage falls as demand drops.
See App Hosting for scaling and billing details.
Does this apply to Cloud VPS?
Cloud VPS lets you choose and resize your VM's CPU and RAM. Performance Guard rebalances workloads between physical hosts, but does not automatically resize your VM when application demand changes.