Available loading method options are limited

We want to use the default loading method for the resource assignments. It looks like the drop down only allows us to select from 3 or 4, which are the no update to past. Is this something we have configured incorrectly?

The methods to allocate planned hours depend on whether or not fiscal periods have been selected for the project, and the loading methods that are specified for tasks. When no fiscal period is selected for a project, only loading method 3 (Manually distribute – no update) and 4 (Auto-distribute – no update to past) are available.