Not really a forensic delay but this is the only "claim" section.  There is a delay caused by a design issue, for example in the structural design review a change is made.  A notice of potential claim is filed.  Say the delay at that time is projected at 6 weeks, after the steel arrives and is installed it is 4 weeks.  A claim is filed for 4 weeks and that there will be cost but the cost is unknown.  The project completes 2 weeks late due to the steel.  I have seen where the contractor asks for the 4 weeks and "reserves the right" to the cost once it is determined.  But now days the contract language requires the cost be submitted at the same time as the delay time.  This creates several problems - if you don't give them the time extension - you are creating a possible "constructive acceleration" plus by spec you likely owe them an answer.  If you force the spec and state they have to give the cost at the same time you would end up paying for the 4 weeks with estimated timeframe instead of the two it actually took.  If you estimate it will take them less time to complete and approve a two week time extension then you have to give them a 2nd time extension if it takes longer - plus the possible "accelleration" issue again.  What is the proper resolution for the owner in your opinion?