Cannot simulate 404 w/Rebalance Recommendation

[brycahta]

Issue

• Users should be able to simulate a 404 on Rebalance Rec until it becomes available
  • this functionality already exists for Spot ITN using mock-delay-sec or mock-trigger-time
• The only way to get 404 response on Rebalance path today is by starting with events subcmd

Desired State

• Users can start AEMM so that RebalanceRec path returns 404, then it eventually returns valid response to simulate an instance "receiving" the Rebalance notice