I suggest applying this phrase once they want back in. You are at a stage where the A has to be confirmed. A long way away from where I am talking.
FYI My W did exactly the same thing with the phone. If you want to make sure just use an excuse to get your hands on it. If he gets defensive that is a red flag. If he cuts out the sound for arriving messages that is a red flag. If he never used to hold on to the phone and now does that is a red flag. If he uses passwords or changes them without telling you or prefers to unlock it himself that is a red flag.
Basically any form of non transparency is a red flag.
Asking him or confronting him will not yield results. So no point doing that. It will only warn him to get better at concealing.
We are creatures of habit and make a lot of mistakes which is why we get caught. I am sure if you want to confirm if he is playing around or not just think back of changes in his habit, lifestyle or agenda.
If he is having a PA he will use the set of events that he has until now to not create suspicion. Suddenly having a new activity will raise questions and he does not want that.
If he is texting a lot chances are it is a new A or at the EA phase. Once the A has gone PA or is in full swing for sometime it turns into a relationship with less txt as they are talking when they meet.
These are imho but if he is clutching the phone then yes, he is doing something he should not. How much he is texting in my view determines if it is an EA or PA and in what phase it is.
