If I modify the date (on Calendar D3), the calendar automatically changes to display the availabilty of each person (cells e5:H31). This is depend on the dates of the daily log (Daily log column G), the times (Daily log column H), and the names (Daily log column I). If one of this values changes, then the calendar does to. However, what I need is that if a person is "Ocupado" (which means busy, btw) at a certain time ((e.g 9:00 AM) obviously because on the log the person is busy at that time, and that date) then he should also be ocupado the next hour (e.g. 9:30 AM). In a nutshell, the shifts are always going to be an hour long, but they can start at 9:30, too; in which case it should be ocupado for 10:00 too.
Solved by C. L. in 26 mins