Okay, it's been seven hundred years since you sent this ask and this isn't all I wanted to draw for this, BUT. In the spirit of not letting you wait any longer: Tim saying goodbye before setting out to search for Bruce. He's a little more stable in this AU, ... possibly because his dad's still alive (that changes depending on my whims), possibly because he's forcing himself to be more communicative for Allie's sake.
Either way, things do get sorta weird between Steph and him the longer he's gone because he's pretty consumed by his mission and when they meet again, it's like "You haven't called in almost a month" and he goes "I've been thinking maybe it's better that way ..." and they get into a very heated argument about it that doesn't get properly resolved for a while but he does call to talk to Allie a few days later, so at least there's that.
I'm not sure they ever fully properly break up in this. It's more Tim pulling away and Steph having to much on her plate to pull him back in and so they have a rough patch and don't talk as much as either of them want to but they're never officially not together. Sort of like when Bruce revealed Tim's identity to Steph ... which also happens differently in this AU but that's another story.
Allie, in this era, of course greatly misses Tim and asks for him constantly but she gets occasionally distracted by Damian, who Steph decides to drag along to just about every outing they have so he gets to be a kid ... I think her and Dick might be closer in this AU, too, just by virtue of Tim being so close to Dick and much more intertwined with Steph. Either way, the kid is very, VERY happy when Tim gets back home permanently and does not let go off his hand for, idk, at least a day. Longer if she didn't need sleep.
Also, Allie is a BIG fan of Cass!Batgirl and absolutely not interested in the blonde impostor running around Gotham now, which is a major blow to Steph's ego and very amusing for everybody else.
Uuh, more later! Gotta draw some Steph-Allie one-on-one time again soon ...