There is no native support for Azure Batch low priority or spot machines. If you create a pool with Batch Forge, you must update the autoscaling formula afterwards to replace with which will change the target nodes to low priority spot machines.

However, due to the limitations of Azure Batch having a pool hang and require manual deleting is a frequent occurrence. This then requires manually recreating the pool. Letting forge create and destroy the pools as required is much cleaner.