Revision On Sheet Renumber override

Hi to all Dynamo and revit Users.
We have to Issue Construction Drawings for a project that i work on. We have introduced revisions numbers which starts with P00 as Alphanumeric system and Numeric which beigns with T00. Now We have to introduce a new revision starting with C00. Thus I would like to know ways which might work out. I have a slight idea by introducing P00 and C00 as numeric system if there is a way to select which of the following to display on my sheet- P00 or C00
Could you give me some good practice answers to this issue. I tried to re create a script with Dynamo which overrides my revisions but it is not working!
Could you help with developing it?

Hi I want to take the Sheets which are having Revision number 95 but the revision is empty list on the end. After I have the sheets with the latest revision I want to modify Number on the sheet which is starting with PXX and override it to CXX. Any clues how to override on sheets revision parameter.