What's happened with Batwoman?

Apologies if this has already been discussed somewhere, but I couldn't find it.

So, last we saw Kate Kane before the new 52 ended was in volume 6 of her self titled series, Batwoman and the Unknowns. At the end of this series, she goes to speak with Maggie, presumably to work things out or end it on good terms.

Flash forward to Detective Comics 934, Rebirth. Her father mentions she's "dated" several women the last few months, but nothing has stuck. No mention of Maggie, from either of them. Batman recruits her, and when he takes her to recruit Clayface, he mentions that she "worked with him before" a clear reference to volume six of her solo series. But as this storyline has gone on, we've seen NO mention of ANY other part of Kate's previous history. No Red Alice, No Hawkfire, No Maggie Sawyer, no mention of her tangling with the DEO and fighting Batman, we don't even get any references to Elegy, which happened prior to the new 52 reboot.

So, what's going on? Did they erase her entire history, except possibly her few appearances during the 52 miniseries? If so, why throw in the Clayface reference? Why make it seem like we're supposed to be acquainted with this character, if she's not the same Batwoman we were reading for seven volumes?