For the past month the show has been posting online old clips and photos that include Paul/DD. Lauralee Bell's social media has included old photos of him. On ET-Canada last week, they asked actors who the best kisser was of the actors they'd kissed during their time on Y&R, and Lauralee Bell picked Paul. I believe other actors have included him in old photos.
The show's dialogue over the past few months has been clearly stating that Paul is active in Genoa City, is still the police chief, and he is still married to Christine:
Paul was discussed in January dialogue between Christine and Danny. Lauren described Paul fondly at her party (TEB anniv episode Jan 25) where Lauren tells Fen's boyfriend about her past, how she was once with Paul, and he's now the police chief - and they showed an old clip of Paul and Lauren during the episode. During Heather&Lucy's recent visit to Genoa City, they told Daniel they'd just visited Paul and Christine, describing a scene that was offscreen.
There seems to be an intent to make Paul part of the show, yet DD isn't.
I've no idea what the behind-the-scenes reasons are for any of this.