Flights for this fare start on August 21 and run through November 6, 2018. Travel is available any day of the week except on Sundays, no minimum stay required. Tickets at this price book into Basic Economy, which limit your carry-on allowance to just one small personal item such as a purse or small backpack that will fit underneath your seat. If you find that too restrictive, on American the Main Cabin fare is only $33 more bringing the flight total to $260, which is still a very good price for a cross-country flight.
Seen below, I found seats departing SFO on Friday, September 7, and returning from MIA on Monday, September 10, 2018. This fare is widely available so you shouldn't have any trouble finding it for your travel dates.
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