If you mean outdoor ones, no, they can start about now.
If you mean indoor ones, then maybe - although they used to be dried off in late spring in the past, newer plants are bred to flower continuously, and I've heard of then flowering for a couple of years with no breaks.
Hi there - we have well established outdoor cyclamens and in the past few days I have noticed 4 or 5 flowers emerge. I do think it's a bit early but this year has been so strange I would not be surpsied by anything - our forsythia produced a second flush of a few flowers about 3 weeks ago - I had to look twice as I could not believe it !!!
Reports on other sites suggest that C. hederifolium this year began in mid July. First of ours was the end of July which is about normal for us, but the main flush is just beginning now.
Yes, our cyclamen hederifolium alba have just started flowering - the same week as last year - the week we moved into the house - it was a wonderful welcome as they're one of my favourite flowers and I had no idea that the garden was stuffed full of them