In an interview with The Kyle and Jackie O Show on Wednesday, Becky said she'd been "seeing someone for a short period of time" when producers came knocking.
"Were you single when they approached you? Or did you have to ditch someone?" radio host Kyle Sandilands asked, prompting the reality TV star and her sister to laugh awkwardly.
"If I was in a relationship, I definitely wouldn't have gone on the show," Becky responded. "I was single, but I was seeing someone for a short period of time there."
Pressing her for further details, Kyle clarified: "Just a bang buddy?" to which Becky replied, "Yeah."
Insisting the pair ended things on "really good terms," Becky said she was as "honest" as she could be when breaking the news to her former flame.
When Kyle asked, "What did you say? 'Look, it's been great rooting you, but I'm going on TV with 30 other blokes?'" Becky shared: "I said to him, 'There's this opportunity that's come up with Elly for me. It's a TV thing, a dating thing. Just to be clear with you, this is what I want to do.'"
Comedian Ed Kavalee was the first to break the news about Becky's relationship history back in August,
"The person that she was with found out she was doing this show from the press," he explained on the Hughesy and Ed radio show.
His co-host Dave Hughes quizzed: "He thought he was in a relationship with the older sister and he's found out that he's no longer in a relationship with her when he saw the press release that she was on The Bachelorette?"
"Yes," he continued, adding that he'd heard the story from "sources" deep in reality TV" and that the gentleman in question agrees there is no bad blood between them.
Although he has declined to be identified, Becky's former beau maintains she "is an incredible woman” and “wishes her nothing but happiness and love on this journey.”
Until recently, the defence contracting specialist who was born and raised in Parkes, NSW, had been nursing a broken heart after finding out the person she was seeing was cheating on her.
“I fell in love with this guy two months before I was leaving for a holiday. He flew over and came to see us at the end of our travels and we spent about a month together,” she told Woman’s Day.
“But when we came home, a month or two afterwards I found out through friends he was mucking around on me.”
"I am told that the guys were pretty understanding about it to start off with. They felt bad for her, but by the end, it actually started to come between them forming a connection with her," Pustetto says.
"One contestant dishes to me, 'Becky spoke about it openly during the show but the boys could tell that she wasn't over it and was still very hurt about what happened. It affected her forming connections with a lot of the guys because she has huge trust issues. She actually said to us, 'I have to go hard on you guys. It was a couple of years ago but I am still really affected by it.'"
Although Becky is a newcomer to the franchise, viewers are already well acquainted with Elly. The mechanic was a firm fan-favourite on astrophysicist Matt Agnew’s season, with the pair immediately bonding over their love for the Parkes Observatory.
The Bachelorette starts on Wednesday at 7.30 pm on Channel 10.