I checked out a copy of Fowler's "Roman Festivals of the Period of the Republic"; he lists no such festival under the name you give, and in fact no festivals in the time period you cite. He also notes the curious lack of any festivals in late October and all of November when presumably an agricultural community had little else to do.
Some references do cite a festival held in honor of Pomona (e.g.
Wikipedia), the Roman goddess of fruit trees (yes, really), held on November 1st (not found in Fowler). Pomona is clearly a rural goddess, and was probably not the occasion of official celebrations at Rome--as was the case with, say, the Saturnalia. However I could imagine her festival being part of general harvest celebrations in parts of rural Italy.
Little is known of this goddess. She was the wife of another obscure god known as Vertumnus/Vortumnus, who gets his name presumably from the changing seasons (
vertere). He attempted to seduce her under a variety of different forms--plowman, reaper, etc.--all associated with the different seasons. She finally gave in at the end of the year--one reference at
Wikipedia again says she was tricked--and we could presume the "fruits" of this seduction are a metaphor for the fruit that trees produce in late autumn (got most of this detail from the Oxford Classical Companion/Dictionary, under the various headings). They are remnants of the more primitive local Roman religion--one strong on animism and natural phenomena--which the adopted Greek religion slowly replaced in urban areas. As a side note, the adoption of Christianity followed a similar pattern in the Roman world, where the religion caught on with city folk long before the stubborn countryside would give up their older beliefs (this is why, for example, non-believers are called
pagani - "country-dwellers, pagans").
Again, other than a few internet sites I can't definitively say there was a Roman festival in honor of Pomona on the 1st of November. But the mythology is true enough, and I think an enterprising student should be able to generate a short article out of at least these ideas...