On March 16, 2021, it was confirmed that Howarth will return to the GH studio and begin filming again in April. It was unknown who he would portray.
On April 1, 2021, it was revealed that Howarth will not be reprising his role of Todd Manning, but at the time it was still unknown who he'd be playing when he returned.
On April 20, 2021, it was confirmed that Howarth will be back on-screen sometime in May, presumably as a new character. His upcoming return is teased to be "extremely memorable." He made his first appearance on May 27, 2021, with his name revealed to be Dr. Austin.
On the latest podcast of Dishing with Digest, it was announced that Austin’s identity will be revealed the week of July 12, 2021 on GH. Austin was revealed to be Dr. Austin Gatlin-Holt on July 13, 2021.
Austin notices Louise isn’t breathing and holds her close to his body until she starts crying. Then he gives her to Maxie who thanks him and says she needs to get to Beechers Corners as someone is waiting there for her.
Austin says that he will take her there if they can stop at the hospital first. He prepares to call for an ambulance but Marie Hopkins hits Austin in the head with a firepoker and knocks him unconscious.
Maxie calls Brook Lynn who arrives in the woods and takes the baby from Maxie. Austin wakes up and asks where the baby is. He is taken by ambulance to GH with Maxie.
On June 15, it was revealed that he owns the Country House that Fake Chloe had taken Maxie to, as well as several other properties in his hometown of Pautauk. Sam McCall and Detective Dante Falconeri are investigating the house and ask Austin about the video camera they find inside. Austin claims that he doesn’t know about it.
On June 18, Austin leads Dante through the woods and tells him he is trying to preserve these woods. He pushes Dante out of the way before he falls into a mine shaft. Austin says there used to be mining in the town. Dante finds a body (presumed to be Marie) at the bottom of the shaft.
On June 28, Valentin Cassadine and Anna Devane visit the Pautauk Woods to look for clues and Austin tries to help them but he doesn’t remember much. He gives Anna the keys to his country house before he leaves. It starts raining so Anna and Valentin go inside the house and Valentin starts a fire. Anna finds a picture of Austin’s family and recognizes his father.
On July 9, Austin is hired by Dr. Britt Westbourne as a doctor at GH. He says that he plans to leave his practice in Pautauk and move to Port Charles.
On July 13, with the help of Scott Baldwin, Austin barged into the ELQ meeting to replace Valentin as CEO, revealing that he is a Quartermaine as his full name is Austin Gatlin-Holt, making him the son of Jimmy Lee Holt and Charity Gatlin and thus the grandson of Edward Quartermaine. Austin said that Jimmy Lee dies six months ago and that what was rightfully his father's is rightfully his, before revealing that he wants to challenge Edward's will, which stated that Jimmy Lee and his descendants are not entitled to any ELQ shares.
On August 3, Detective Harrison Chase and Austin learned that Michael Corinthos and Willow Tait have been sleeping together behind his back. Upon learning this information, Austin began to manipulate Chase into getting some form of revenge on the two of them.
On August 20, Austin had Chase steal Edward's letter which was about Edward reconsidering his decision about Jimmy Lee and was thinking about adding him and his descendants back into his will. When Willow and Michael finally came clean to Chase, he revealed to them that he can walk and admitted to finding the letter for Austin. Willow and Michael begged Chase not to give the letter to Austin, but Chase decided that he didn't need this, gave the letter to Michael and told him to do whatever he wanted with it. Michael later decided to give Austin the letter.
On August 23, Olivia Quartermaine took her son, Leo Falconeri to see Austin after Leo cut his finger. After examining Leo and patching him up, Austin wanted Olivia to schedule a follow-up and gave Leo a fidget spinner to play with. After they left, Austin said that it was really important that he should see Leo again.
In October, after Brook Lynn asked Austin about Leo, Austin ended up revealing to her that he thinks Leo may have autism. Using this to her advantage, Brook Lynn got Austin suspended from GH due to violating HIPPA, which upset Austin. Brook Lynn then gave Austin a choice - he could either choose his medical career or choose to fight for his and his father's claim to ELQ.
On October 21, Austin signed away his claim to ELQ shares because he loved being a doctor. Before he left the Quartermaine Mansion, he declared war on Brook Lynn and said that this wasn't over.
Pushed Det. Dante Falconeri to prevent him from falling into a mine shaft [Jun 18, 2021]