I have had interviews which started in Mid Feb and extended through to the end of April. The heaviest period seems mid March to Mid April. While it would be good to get vacation time then, an even better move would be to get an elective or ambulatory month for either or both of march and april. Pick something were they don't really need you to show up. This would make getting away to interviews way easier.
Try to get some vacation time in March. For sure, you'll probaby have some of your interview invites @that time. There are a few places that interview in Feb, and a few as late as early may, but mostly it is March and April.