Sometimes, and sometimes not — it depends on where your hair is starting and what it has been through. Lifting more than a few levels safely is usually two sessions, six to eight weeks apart, with bond repair in between. You will be told honestly which one you are, before anything is booked.
Not a problem, but it does change the plan. Box color sits differently in the strand and can band when it lifts. Bring photos to a consultation and it will be mapped out properly.
Balayage and lived-in placements are designed for three to five months. Root touch-ups run four to six weeks. A gloss between appointments will noticeably extend all of them.