@emilia May we know just why you have decided to spay her now ?
Unless spaying her is going to substantially improve her quality of life, I would advise against it.
My 7 month old girl has just come into her 1st season. She lives with 2 neutered male dogs(not Basenjis) and so far they're leaving her alone. I've booked her in for spaying in 3 days time. What do others think? Should I let her finish this heat cycle and get her done later?
The advice we have been given and that we followed is this: spaying exactly between two heats, because at that point she is in a balanced hormonal state. To spay her now would put her system off balance. I would strongly recommend you cancel the meeting and wait at least 4 months or so.
Most Vets will not recommend spay during season and unless there is a medical reason for doing it now, will recommend waiting till she is at least 3 to 4 weeks past the end of her season. I would also agree you should put it off and wait. Keep in mind however the neutered males can achieve a tie with a bitch in season, however considered "safe sex"… but since you have two males, this could present a problem, so something to keep an eye on