Can i change my Collections level for Operating unit

Background:

Currently, we have Collection Methods to be defined for Operating unit as 'No'. In other words, all operating units in Oracle instance follows 'one' collection method which is 'Strategies'. 

Question:

I have reviewed various discussions and white paper and guidance provided by Christine Rogers of Oracle which I believe are all about changing 'collection level' and not 'collection method', hence this question:

We are planning to modify collections setup questionnaire checklist and change the collection method from 'Strategies' to 'Dunning Plan and Strategies'. We are not planning to change the collection level which is currently defined at 'account level'.