Ive been punting, intermittently, for a long time. I dont think theres any justifiable reason why a sp makes unsolicited calls or texts. It happened to me once and it took a shit load of quick thinking and acting to get out of it and even then my wife at the time wasnt entirely convinced. Having a punting phone is even lore risky imo as the potential for discovery is ever present. The best solution as far as i can see, has already been suggested - set phone to do not disturb except for certain contacts between whatever hours suit you and minimise notification visibility.
Its inexcusable for them to contact you unsolicited. They're not idiots, they know the score but tje consequences arent theirs to bear.