When can I Change the House Locks?

My STBX has taken our kids an hour away to a family friend’s house.
It is a School Night. This is an unheard of action in our marriage.
At first my kids would not tell me where they were, nor my wife, then later my wife left me a voice mail saying where they were.
I was out of town this weekend, just came home this morning.

Last Year, my wife left with our children without letting me know where they were, she gave me every sign she was leaving for good.
I changed the locks due to a lawyer’s advice.
We got back together two months later.

She has said this time, “they are only staying the night”, however I do not believe her, as she said this last time, as she was buying time to put her plan into action (leaving me and taking our kids without my permission).
I want to change the locks now, but she has not showed the clear signs (yet),

At WHAT point am I in my rights to Change the Locks ?
Due to my wife taking our kids, not telling me where they are (at first for 4 hours), on a school night,
I can not see her taking our kids to school tomorrow as she is too far away.

Once your wife moves out (packs her clothing and personal belongings) you may change the locks.

You will also want to file an action for child custody in the near future to ensure you are awarded adequate time with the children, and to set up the parameters of the same. I suggest you set up a meeting with an attorney in the near future to formulate a plan of action.