I just wanted to add what the recommended Honeybee workflow is for making IDF-type schedules that are at finer timesteps. All that you have to do is take the schedIDFText output from any of the schedule-making components and edit the text so that and of the !- Time values are going to a time other than something that falls on the hour (like 6:30 instead of 6:00). Then you can just write that text to the GH doc memory using the Add EP Objects component like so:
When you assign this to a HBZone, it will obey the finer timestep of your edits.
Unfortunately, EnergyPlus does not support CSV schedules that are at a finer timestep than an hour as noted in the documentation: https://bigladdersoftware.com/epx/docs/8-9/input-output-reference/group-schedules.html#schedulefile
So hopefully the IDF-type schedules are good enough for what you need.