I don't like Patrick coaching Grigor from the start, he doesn't have a successful record with Jeremy, Baggy, or even Laura. These players have been improving in the ranking when they left him. Anyway, I find Serena taking Patrick away from Grigor is a good news. Finding a good new coach takes sometime, so papa Dimitrov may step in, like he does at times. I'll report to you guys as soon as I find out who's he's with in Bangkok.
PS. Serena's success (with Patrick) is overrated. She can win Slams with anybody when she puts her focus on training. Patrick just enjoys free publicity.