Dynamically updating / changing CSV files from an Excel worksheet

[Manexcel]

I have a macro enabled workbook that is used to manage room(3) allocations. I would now like to upload to a google calendar. I understand that goggle calendar requires a .csv file format. The main worksheet, Year 2019, is made up of many rows for the complete year (>2500) e.g.

01Jan19
to 31Jan19
.
.
01Dec19
to 31Dec19


Each day of month e.g. 01Jan19, may have repeated one or more entries (depending on room allocations)

The main column headings are ;

start date - subject - who booked - start time - end time - description

example year 2019 sheet

01Jan19 - subject 1 - fred - 0900 - 1100 - meeting 1
01Jan19 - subject 2 - Mary - 1200-1400 - meeting 2
01Jan19 - subject 3 - Harry - 0900-1100 - meeting 3
01Jan19 - subject 4 - John - 1400-1600 - meeting 4
02apr19 - subject 1 - fred - 0900 - 1100 - meeting 1
02apr19 - subject 2 - Mary - 1200-1400 - meeting 2
31Nov19 - subject 3 - Harry - 0900-1100 - meeting 1
etc

When I update / create a new entry in the Year 2019 sheet I would like a process (formula?), to automatically update a .csv file, one for each month of the year, which would then be ready for importing into a goggle calendar. I would only update the goggle calendar for those months that have changes in them.

I understand that google calendar requires a .csv file with row headings of;

subject - start date - start time - end date- end time - all day event - description - location - private

As always I thank you in anticipation for your time and effort