Set Job Info Parameter from Custom Event

How do you set the value for a Job Info Parameter within a deadline event? There is only the method to retrieve the values, but not to set or change them?

job.GetJobInfoKeyValue('ChunkSize')

I need a way to change this within a deadline event.

I see there is also job.JobFramesPerTask which appears to be the same as ChunkSize. However there is no setter for this property either.

Unfortunately it appears that you cannot modify this property once the job is submitted. You cannot change it from the Monitor, either.