Ordering of unknowns(system) in MTK when array-valued variables are scalarized via structural_simplify

Specific Domains Modelling & Simulations
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Ordering of symbols is not guaranteed after symbolic transformations, and parameters are now stored in a custom MTKParameters object instead of a vector.
Frequently Asked Questions · ModelingToolkit.jl

So no, you cannot swap ordering, and you don’t need to swap the order if you use symbolic indexing, for example sol[sys.Φ_s_c[2]].