How do i determine the fiscal year of my LLC in Delaware? Is it the
date the company was created or do i choose it and how can i let the
state know? Is there any criteria on which i should choose it?

Dear orizon,

Sorry I could find no mention fo fiscal year definition in the act
Delaware Code : TITLE 6 Commerce and Trade : SUBTITLE II Other Laws
Relating to Commerce and Trade : CHAPTER 18. LIMITED LIABILITY COMPANY
ACT...

http://198.187.128.12/delaware/lpext.dll?f=templates&fn=fs-main.htm&2.0

The calendar year, is the default requirement for S corporations.
Although, this may be ammended for good business reasons such as
uneven distribution of income.

I expect that another researcher will provide more assistance.

Regards,