Jotform Submission ID - 2x Quick Questions

I have 2x questions about the JotForm submission ID:

1.) Is this number 100% unique? i.e. not just unique when compared to other submissions for that particular form, but unique in the WHOLE jotform universe. Unique when compared to all submissions, from all forms, created by all customers.

2.) Could the ID attached to a submission change at any point in the future for any reason. Or is it fixed once the submission has been generated?

Many thanks.

1. The ID is universally unique in the whole jotform ecosystem

2. Once the submissions ID is generated it will remain persistent throughout and wont change at any point in time