The cycle length is 2019 at the moment. This means there are 2019 verifiers validating transactions, they take turns producing blocks in a circular order. Each time a full cycle of verification ends, a new verifier joins the cycle. (This verifier is chosen randomly from the ones waiting in the queue), increasing the cycle length by one.

On average, each cycle of verification lasts 7 times the length of the cycle, in seconds. It is important to note that the amount of time it takes to complete a full cycle does not affect the finality time for a transaction.

You can learn more about Nyzo here:

http://tech.nyzo.co/