Key legal question
Whether the appeal against the road-category designation was admissible despite being a preliminary decision.
Extracted holding
The designation was only an interlocutory decision; no irreparable harm was shown, so the appeal was inadmissible.
Extracted reasoning
Road categorization did not yet determine the appellants' contribution liability. The binding allocation of costs would arise only later in a contribution plan or separate order, which would itself be appealable.