TIME conversion from 0FISCPER to BPC format

Hi Experts,

I need to convert the Time format as attached.

I have an issue at the months from 10,11,12. For Ex, if external 0FISCPER is 2019010, it should be incremented to next year as 2020.01, 2010011 should be 2020.02 and so on... in BPC.

How do I increment the years here? Any suggestions would be helpful.

time-conv.png