DP application to NI question

I am applying for my DP Certification and I have a question about the sea time filing on the website. It ask for the [U]Dates of Arrive and the Departure[/U], then automatically calculates the time and logs it as hours of familiarization. What If you spend 30 days onboard and only have 10 days of DP time. How can I make the online application reflect that, or do I not need too? Do they just use that to verify time on-board a vessel and use the company DP Sea time letter for actual DP time?