Product Posting With "Date Available"

I have problem with product posting .....
When i add product and I completed requirement fields for upload but "Date Available" I follow that not edit when i test on store front doesn't show why?

but when I click "field: Date Available" and Rollback one day is display....

Ex: today is 02.02.2016... I'm uploading one product for today '02.02.2016' that automatic. but haven't show....
format: dd.mm.yyyy
if I change field "Date Available" to 01.02.2016 for today show why and how to resolve?

Date Available field pre-fills with your system time (your Local time), but opencart shows products based on the server time. Seems you and your server timezone is different and your timezone is ahead than server time. So consider server time while you insert products.