STOCKHOLDERS EQUITY AND LOSS PER SHARE - Basic and diluted net (loss) income per share (Details) - USD ($) $ in Thousands		12 Months Ended
	Sep. 27, 2021	Sep. 30, 2023	Sep. 30, 2022
Numerator:
Consolidated net loss		$ (104,902)	$ (337,262)
Less: Net income (loss) attributable to noncontrolling interests		238	(244)
Net loss attributable to common shareholders		$ (105,140)	$ (337,018)
Denominator:
Weighted-average shares outstanding - Basic (in shares)		25,641,000	24,354,000
Weighted-average shares outstanding - Diluted (in shares)		25,641,000	24,354,000
Anti-dilutive common share equivalents (in shares)		5,763,000	5,540,000
Shares issuable upon conversion (in shares)	3,040,268