It’s generally more expensive to depart on a Sunday, if you have to leave on this day you can still search on Cheapflights to find great options that meet your needs.
Due to multiple factors, expect to potentially pay more when booking in June. For low rates, February can be a great choice for travel to Warsaw. Flights to Warsaw from Greenville in February are about $919 on average during February, but can be found for as low as $520.
When flying from Greenville to Warsaw, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.