Good luck with your journey! There is no way of predicting how many cycles u will need but what others have already mentioned I agree with. Don't be afraid to change FS if it's not working.
Took me my 4th transfer to get DS. 1st stim got 1 fresh and 2 frozen transfer BFNs. Changed clinic and FS and got DS as fresh transfer from 2nd stim. Got 3 blasty in the freezer and am working my way thru them ttc #2