Does my boyfriends bm want him back or is this normal ?

My bf and his bm share a 3& 4 year old . They have always been great coparents since we started dating 2 years ago however this year she has started being more “friendly” I guess the word is .

The last 2 years they did birthdays separately , it was just drop off and pick up on their days like clock work . They barely spoke and if they did it was just emergencies and updates on the kids . That’s it .

January of this year she proposed they do birthdays together and have family days . He agreed to do the birthdays together after we had a talk about it but not the family days . She told his mom she misses what they had but mostly just wants their kids to see both parents together.

Lately she has been calling him more about random stuff . Talk about the kids, venting about life/work , planning birthdays and events for the kids, future sports they will be in , school events etc. mostly about the kids .

Monday they dropped their son off to preschool, drove separately but did it together. Then she went alone to drop their daughter off at daycare .

I have been ok with this up until yesterday . Yesterday she called him to say she’s moving and asked if he could help her move , asked how our relationship was doing and if he planned to marry me , and said that her and her new best friend talk about him all the time and that he should meet her and that he need him to have their kids for a week cuz she’s going on a trip for her birthday and talked about where she was going what she bought to wear and stuff . The call was almost an hour long .

My older sister says she’s probably just appreciating the fact they are cooler now and doesn’t realize she’s over doing it . My boyfriend thinks she wants him back and we had a talk about it last night . He says it makes him just as uncomfortable as it does me and asked how he should go about telling her .

I was wondering if someone can please tell me the line between healthy coparents and when it becomes inappropriate? I know for some this is normal . Any tips on what he should do as well ? Thanks

@chantelle I was present for the home call and he communicates with me . Plus he tried to hang up several times and was very dry with her . But I agree Inappropriate I do want them to coparent but they are not besties !