I have some other copy of Ubuntu 24.10 installed in different partitions but installer detects only one 24.10 and one 24.04.
See attached screenshot of screen 'Manual partitioning'.
Here the output of 'update-grub' from another partition:
corrado@corrado-n16-oo-0810:~$ sudo update-grub
[sudo] password for corrado:
Sourcing file `/etc/default/grub'
Generating grub configuration file ...
Found background image: jumping-n16.png
Found linux image: /boot/vmlinuz-6.8.0-31-generic
Found initrd image: /boot/initrd.img-6.8.0-31-generic
Found memtest86+ 64bit EFI image: /boot/memtest86+x64.efi
Warning: os-prober will be executed to detect other bootable partitions.
Its output will be used to detect bootable binaries on them and create new boot entries.
Found Ubuntu Oracular Oriole (development branch) (24.10) on /dev/nvme0n1p2
Found Ubuntu Oracular Oriole (development branch) (24.10) on /dev/nvme0n1p3
Found Ubuntu Oracular Oriole (development branch) (24.10) on /dev/nvme0n1p4
Found Ubuntu Oracular Oriole (development branch) (24.10) on /dev/nvme0n1p5
Found Ubuntu Oracular Oriole (development branch) (24.10) on /dev/nvme0n1p7
Found Ubuntu 24.04 LTS (24.04) on /dev/nvme1n1p2
Found Ubuntu Oracular Oriole (development branch) (24.10) on /dev/nvme1n1p3
Adding boot menu entry for UEFI Firmware Settings ...
done
corrado@corrado-n16-oo-0810:~$
ProblemType: Bug
DistroRelease: Ubuntu 24.10
Package: subiquity (unknown)
ProcVersionSignature: Ubuntu 6.8.0-31.31-generic 6.8.1
Uname: Linux 6.8.0-31-generic x86_64
NonfreeKernelModules: zfs
ApportVersion: 2.30.0-0ubuntu1
Architecture: amd64
CasperMD5CheckResult: pass
CasperVersion: 1.501
CloudArchitecture: x86_64
CloudID: nocloud
CloudName: unknown
CloudPlatform: nocloud
CloudSubPlatform: seed-dir (/var/lib/cloud/seed/nocloud)
CurrentDesktop: ubuntu:GNOME
Date: Wed Aug 21 10:40:38 2024
DesktopInstallerRev: 237
LiveMediaBuild: Ubuntu 24.10 "Oracular Oriole" - Daily amd64 (20240821)
MachineType: ASUS System Product Name
ProcEnviron:
LANG=C.UTF-8
PATH=(custom, no user)
SHELL=/bin/bash
TERM=xterm-256color
XDG_RUNTIME_DIR=<set>
ProcKernelCmdLine: BOOT_IMAGE=/casper/vmlinuz --- quiet splash
RebootRequiredPkgs: Error: path contained symlinks.
SnapUpdated: False
SnapVersion: unknown
SourcePackage: subiquity
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 04/01/2022
dmi.bios.release: 14.2
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: 1402
dmi.board.asset.tag: Default string
dmi.board.name: PRIME H610M-E D4
dmi.board.vendor: ASUSTeK COMPUTER INC.
dmi.board.version: Rev 1.xx
dmi.chassis.asset.tag: Default string
dmi.chassis.type: 3
dmi.chassis.vendor: Default string
dmi.chassis.version: Default string
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr1402:bd04/01/2022:br14.2:svnASUS:pnSystemProductName:pvrSystemVersion:rvnASUSTeKCOMPUTERINC.:rnPRIMEH610M-ED4:rvrRev1.xx:cvnDefaultstring:ct3:cvrDefaultstring:skuSKU:
dmi.product.family: To be filled by O.E.M.
dmi.product.name: System Product Name
dmi.product.sku: SKU
dmi.product.version: System Version
dmi.sys.vendor: ASUS
Note: the only OS detected was an Ubuntu 24.04 on another volume and an old installation on partition nvme1n1p3 dated 2024-07-12.
More recent installations are not detected. To try clarify the problem i ran another install and now no system is recognized.
The only system previously detected on partition nvme1n1p3 is now a new install, so not detected.
Conclusion: install does not detect Ubuntu 24.10 installed from recent ISOs.