Rare event prediction on time series that change structure mid-stream? [D]

Hi reddit! I made this post on r/MLQuestions, but I am posting it here too for spread This is a case I have been assigned at work and I'd love input from anyone who's tackled something similar. I'm building a failure prediction model for ~33k chargers. The devices emit data at two very different rates depending on operational state: roughly 1 obs/hour when idle and 1 obs/20s when active with a different feature set in each mode. I want to try predicting failures within a 7 day horizon, but I am open for other suggestions.