Emission maps for three simulations (labeled in the sub-figures) at times ∼10 Myr earlier than those presented in Figs. 4(A-C), reiterated in the bottom row. A comparison between these temporal snapshots underscores the dynamic and transient nature of filamentary structures within the cocoon, while also aiding in constraining the typical lifetimes of these multi-scaled internal features. For further details, refer to Section 5.3.