I too increased my FTP about 30% (very sucky last sept.) from mid nov. to mid april where I had a short and shallow peak, earning my upgrade. I then spent may and june training for a stage race and peaked huge bringing my FTP up another 5 % and having the strongest 5 weeks of my short racing life.
I'll be starting "real" training the first week of Nov. focused on 1-2 SST sessions, 1 day of threshold climbs (3-6' climbs) and one long day (4-5 hours) on the fixed gear, MTB or CX. A few group rides and CX races peppered throughout to keep the top end familiar enough.
But, SST is the hot ****! ...for me at least.
-L