This is the first time Harper has been back on the road for the company since this past spring. He has been away from the WWE storylines since August 2018 when Rowan went down with an injury. Rowan has since returned and teamed with Daniel Bryan.
Harper announced in a tweet back on April 16 that he had requested his release over unhappiness with how he's been used, but it was not granted. Harper had been regularly pitching ideas to WWE officials while he was out with the injury, and at one point they had plans for him to feud with Sami Zayn, but they turned every pitch down. Harper was cleared to return to the ring back on February 6, but WWE wasn't using him beyond the WrestleMania 35 Axxess tapings where he faced Dominik Dijakovic. Vince McMahon reportedly just randomly wanted to know why Harper wasn't in the 6th Annual Andre the Giant Memorial Battle Royal at WrestleMania, which is why he was added to that match.
It was reported back in early May that Harper had asked Vince if he could be released from his contract in November, if WWE wasn't going to use him, but Vince told him to take it up with Triple H. It was also reported that WWE officials chose to add 6 months to Harper's contract to make up for the time he spent on the shelf after wrist surgery, and the contract was to expire in November. As of early May, it was believed that WWE was paying Harper to just sit at home as he had been given no future bookings. It was also believed before that Harper won't be able to leave the company until around WrestleMania 36 time in 2020.
There's no word yet on if WWE has plans for Harper to return to action this week, but it's worth noting that he is back on the road with them. Bray Wyatt indicated on Twitter back in May that he had been trying to put together a reunion of The Wyatt Family. Harper is still listed on the SmackDown roster as of this writing.