Hi Hotwaterbottle :)
I'm just really concerned that you will miss this opportunity to have black-and-white evidence of your STBXH's dodginess.
What if the iPhone isn't there anymore?
And you have to wait nearly a week?
I'm just saying that if and only if your STBXH turns out to play dirty like my XH has, you need all the evidence you can possibly get to support you, and this is a crucial event in that your STBXH has done / is doing something illegal- so you are entitled to get the police involved.
I can't tell you how relieved I am that I once reported XH to the police a year before your separation. That police report from years ago is worth so much right now as it shows that I haven't just suddenly started to make up allegations but that there was something dark going on back then already.
If it wasn't for that one police report from years ago, I think it would be much easier for the people, including the Judge, to discount my allegations as something I made up after-the-fact.
I'm only giving you advice based on the worst case scenario that your STBXH will play it dirty just like mine has. In fact, he is factually already playing it dirty --- tracking your car FFS!
I would advice you to reconsider and .... yes, you might lose a good friend over this but if he/she was truly a good friend, they should understand that your XH has broken the law with his actions and that it is a police matter!
At the end of the day, it is a choice between losing your friend's trust and losing your proper access to your children.
This is my honest view. I want to also add that I have lost about 95% of people I considered my friends bit by bit after my separation from XH, especially as the court proceedings started. XH has simply turned anyone and everyone against me who will listen, and that it is well possible that you will end up losing this friendship anyway, at which point you may be kicking yourself for having played it nice and taken your friend's trust into consideration. Don't get me wrong, I'm loyal to a fault, but this very loyalty is what got me into trouble, not wanting to badmouth my XH and protecting his image while he went behind the scenes convincing others that I was doing something absolutely horrifying with regards to how I 'treated' him (by reporting his bust-in at my flat to the cops and finally taking him to court to get proper access to DS).
I lost some friends that I considered some of my very best friends, along with a gazillion acquaintances. I never thought it would come to that.
In black and white, your situation is this: you know XH is engaging in illegal activity. It is your duty to report it. It is your friend's duty to give the police an honest account of what they heard. If your friend has a problem with this, it really is your friend's problem. It is not your problem. You are doing your duty which is to report a criminal activity. To not get the police involved means risking losing a crucial piece of evidence about your XH's dirty tactics. He is already playing it dirty, and it will be something of a miracle if he suddenly out of the blue starts playing it nice. My experience is that they only keep playing it dirtier and dirtier and dirtier and the stakes get raised.
I sincerely hope you will consider this view and seriously consider calling the police ASAP to report your XH's criminal activity. I wish I had read other people's experiences with regards to divorce and child arrangements when all the trouble started so that I could have learned from their advice but no, I made my own mistakes first by being naive and loyal to people, and the only consolation I get now is if somebody else can use my experience to their advantage in fighting for what it right.