Third-party tracking tools have recorded above average position changes across multiple Yandex regions over the previous week, although none of the data shifts have been substantial enough to warrant a rumoured update (based on historical data).
The Yandex search forums are also reporting fluctuations with their rankings.
It is worth noting that we are due an IKS update (based on previous update frequency), so there could potentially be an update brewing as we haven’t had a major update confirmed since Vega, or since the introduction of YATI.