The pace bowler has secured 309 Test scalps in 71 appearances with an impressive average.
Australia's chief selector the selector has confirmed that skipper Cummins will have a crucial role in this winter's historic rivalry.
There were concerns that the veteran bowler might sit out due to a ongoing back issue that remained unresolved.
Initial reports from team management suggested no official announcement had been made regarding his involvement, with the Test matches kicking off on 21 November in Perth.
Bailey expressed that the captain is progressing and remained hopeful about the prospects of participating.
"It's clear that the window is narrowing and there are permutations around that, not only his injury, but additional elements," the selector added.
"It's positive. We firmly believe that he's going to play a key capacity. Hopefully from the opening match. Should that not happen, we'll adjust."
Past Concerns
Cummins was ruled out Australia's limited-overs series against New Zealand and India recently after examinations confirmed a lumbar bone stress.
There is a track record of recurring issues, with flare-ups in multiple past seasons leading to absences from three Australian summers in four years.
He emphasized he would be bold in recovery efforts in his comeback strategy to secure his spot for the Ashes.
Bailey noted that there was no confirmation if he had started his bowling workouts as part of his rehabilitation but acknowledged it was "getting tight" for him to recover fully for the opener.
Alternative Arrangements
Should Cummins not be fit, former captain Steve Smith will assume leadership.
Versatile player Green was excluded lately from the ODI lineup for their ODI contests against the subcontinent side as a precautionary measure because of an abdominal issue.
Bailey described it as a "slight concern and mentioned that he'll feature in the Sheffield Shield, so will be "in a good place to be ready to bowl."
"Extensive planning has gone into creating the schedule for him to participate for the first Test as an all-rounder," Bailey explained.
"He was only going to play the starting games anyway. How he handles the cricket bat in white-ball cricket, even if it just sets him back for another day, the choice was made to adopt a safer strategy."
Match Calendar
The Ashes: Australia v England
From November 21, 2025 to January 7, 2026