The pace bowler has claimed 309 Test scalps in 71 Test matches with an stellar bowling average.
Australia's selection chief Bailey has declared that pace spearhead Cummins will play a "major part" in the upcoming Ashes series.
Speculation had been growing that Cummins might miss the series due to a ongoing back issue that was still troubling him.
Previous updates from the squad suggested no final decision had been made regarding whether he would play, with the five-Test series scheduled to begin on 21 November in Perth.
Bailey expressed that Cummins is "building up" and was "optimistic" about his chances of taking part.
"It's clear that the clock is ticking and various factors at play, aside from the back issue, but other factors as well," he commented.
"The outlook is good. There's strong faith that he'll participate in a major part. Hopefully from the opening match. Should that not happen, then we'll pick it up."
Previous Setbacks
Cummins was ruled out the white-ball matches against New Zealand and India recently after examinations confirmed a lower back issue.
He has a history of back injuries, with recurrences in 2012-13, 2013-14 and 2015-16 leading to absences from multiple domestic campaigns in a limited period.
The bowler mentioned he would be bold in recovery efforts in his comeback strategy to ensure his availability for the Ashes.
The selector indicated that there was no confirmation if he had started his bowling workouts as part of his recovery but admitted it was "becoming urgent" for him to be fit for the first Test.
Backup Options
Should Cummins not be fit, ex-skipper Smith will take over the captaincy.
All-rounder Cameron Green was recently pulled out from Australia's squad for their limited-overs matches against the Asian giants as a safety move because of an abdominal issue.
Bailey described it as a "small issue and confirmed that he'll feature in the domestic first-class competition, so will be "well-prepared to deliver overs."
"Extensive planning has gone into creating the schedule for him to be available for the initial game as an dual-role player," the selector detailed.
"He was only going to play the initial matches anyway. His aggressive style the bat in limited-overs, even if it just sets him back for a short period, the choice was made to approach this more conservatively."
Series Schedule
The Ashes: Australia v England
Spanning from late 2025 to early 2026
