Seasonality certainly has an impact on consumer behaviour on Google Shopping.
During events such as the run-up to Christmas, Black Friday, January Sales, etc it is more important to have up-to-date information on pricing. During these events, some competitors might change their pricing multiple times over the day. It’s imperative that during seasonal events that the prices are checked more often. My strategy for this is to do an AM and PM price check and adjust bids at the beginning and end of the day. Ensure your communication with your client is as clear as ever and ensure product pricing is adjusted regularly in response to what competitors are doing.