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In theory, the shortest practical time from spacecraft separation would be about five and a quarter hours, which is half of a geosynchronous transfer orbit. At apogee, which is carefully placed to occur over the equator, a single burn raises the perigee and changes the inclination of the orbit, and you're there. All early GEO birds used this approach, and many launches still do, especially from near the equator (Ariane, Sea Launch).
SES-8 went to a supersynchronous transfer orbit, which allows for much lower ΔVΔV to change the inclination, since the spacecraft is going so much slower at apogee. It would be 1800 m/s from GTO, but it's 1500 m/s from SSTO. That includes some inclination assistance from the Falcon upper stage, which reduced the inclination from 28° in the parking orbit to 20.75° in SSTO. The SSTO in this case is 295 km x 80000 km.
The SSTO approach takes longer, and there are several maneuvers required. But it is usually well worth it to save that fuel for extending the useful life of the spacecraft. Lifetime is money. A supersynchronous transfer orbit was first used in 1992. SES-8 will perform five maneuvers over two weeks to get into GEO.
Firing the satellite’s main thruster when the satellite is at its apogee has the effect of raising the perigee, and by doing this four or five times, the perigee is raised to the same altitude as the apogee, resulting in a circular orbit. In the case of Intelsat 30, it is expected to take about eight days to accomplish the orbit raising.
