I'll echo this and mention that for those unfamiliar with booking with Southwest (especially on points), it makes sense to basically check your pending flights each day. Southwest will save recent searches so it takes me about 30 seconds to check each morning and afternoon...I do it twice a day

haha. I currently have 2 pending SW flights coming up already booked and if I see an opportunity to rebook and save points I jump on it.
EDIT: I'll also mention that those click-bait articles that say flights are cheapest to book (or check) on Tuesday OR booking 3 months 8 days out is the best time, etc. are garbage advice with Southwest (and probably garbage advice period). I've found the BEST price on SW flights booking the day they are released (they never went down) AND in other scenarios I've rebooked as late as the week of the flight and saved points AND anywhere in between there in other scenarios. I've also found SW flights cheapest on Mondays, Wednesdays, Fridays, Saturdays...you get the picture...