[HTC One A9] bogdan#:
I made TWRP backup of boot/recovery/system and there is some information about partitions in the log file.

Partition Logs:

/system | /dev/block/mmcblk0p61 | Size: 3044MB Used: 3027MB Free: 17MB Backup Size: 3027MB

Flags: Can_Be_Mounted Can_Be_Wiped Can_Be_Backed_Up Wipe_Available_in_GUI IsPresent

Primary_Block_Device: /dev/block/mmcblk0p61

Display_Name: System

Storage_Name: System

Backup_Path: /system

Backup_Name: system

Backup_Display_Name: System

Storage_Path: /system

Current_File_System: ext4

Fstab_File_System: ext4

Backup_Method: files

/system_image | /dev/block/mmcblk0p61 | Size: 3168MB

Flags: Can_Be_Backed_Up IsPresent Can_Flash_Img

Primary_Block_Device: /dev/block/mmcblk0p61

Display_Name: System Image

Storage_Name: system_image

Backup_Path: /system_image

Backup_Name: system_image

Backup_Display_Name: System Image

Storage_Path: /system_image

Current_File_System: emmc

Fstab_File_System: emmc

Backup_Method: dd

/cache | /dev/block/mmcblk0p58 | Size: 247MB Used: 0MB Free: 247MB Backup Size: 0MB

Flags: Can_Be_Mounted Can_Be_Wiped Can_Be_Backed_Up Wipe_During_Factory_Reset Wipe_Available_in_GUI IsPresent

Primary_Block_Device: /dev/block/mmcblk0p58

Display_Name: Cache

Storage_Name: Cache

Backup_Path: /cache

Backup_Name: cache

Backup_Display_Name: Cache

Storage_Path: /cache

Current_File_System: ext4

Fstab_File_System: ext4

Backup_Method: files

/data | /dev/block/mmcblk0p62 | Size: 25472MB

Flags: Can_Be_Wiped Can_Be_Backed_Up Wipe_During_Factory_Reset Wipe_Available_in_GUI IsPresent Can_Be_Encrypted Is_Encrypted Has_Data_Media Can_Encrypt_Backup Use_Userdata_Encryption Is_Storage Is_Settings_Storage

Symlink_Path: /data/media

Symlink_Mount_Point: /sdcard

Primary_Block_Device: /dev/block/mmcblk0p62

Crypto_Key_Location: /dev/block/bootdevice/by-name/extra

Length: -16384

Display_Name: data

Storage_Name: Internal Storage

Backup_Path: /data

Backup_Name: data

Backup_Display_Name: Data

Storage_Path: /data/media

Current_File_System: emmc

Fstab_File_System: ext4

Backup_Method: dd

MTP_Storage_ID: 65539

/boot | /dev/block/mmcblk0p59 | Size: 64MB

Flags: Can_Be_Backed_Up IsPresent Can_Flash_Img

Primary_Block_Device: /dev/block/mmcblk0p59

Display_Name: Boot

Storage_Name: boot

Backup_Path: /boot

Backup_Name: boot

Backup_Display_Name: Boot

Storage_Path: /boot

Current_File_System: emmc

Fstab_File_System: emmc

Backup_Method: dd

/recovery | /dev/block/mmcblk0p60 | Size: 64MB

Flags: Can_Be_Backed_Up IsPresent Can_Flash_Img

Primary_Block_Device: /dev/block/mmcblk0p60

Display_Name: Recovery

Storage_Name: recovery

Backup_Path: /recovery

Backup_Name: recovery

Backup_Display_Name: Recovery

Storage_Path: /recovery

Current_File_System: emmc

Fstab_File_System: emmc

Backup_Method: dd

/misc | /dev/block/mmcblk0p28 | Size: 1MB

Flags: IsPresent

Primary_Block_Device: /dev/block/mmcblk0p28

Display_Name: misc

Storage_Name: misc

Backup_Path: /misc

Backup_Name: misc

Backup_Display_Name: misc

Storage_Path: /misc

Current_File_System: emmc

Fstab_File_System: emmc

Backup_Method: dd

/devlog | /dev/block/mmcblk0p32 | Size: 25MB Used: 22MB Free: 3MB Backup Size: 22MB

Flags: Can_Be_Mounted Can_Be_Wiped IsPresent

Primary_Block_Device: /dev/block/mmcblk0p32

Display_Name: devlog

Storage_Name: devlog

Backup_Path: /devlog

Backup_Name: devlog

Backup_Display_Name: devlog

Storage_Path: /devlog

Current_File_System: ext4

Fstab_File_System: ext4

Backup_Method: files

/carrier | /dev/block/mmcblk0p46 | Size: 40MB Used: 0MB Free: 39MB Backup Size: 0MB

Flags: Can_Be_Mounted Can_Be_Wiped IsPresent

Primary_Block_Device: /dev/block/mmcblk0p46

Display_Name: carrier

Storage_Name: carrier

Backup_Path: /carrier

Backup_Name: carrier

Backup_Display_Name: carrier

Storage_Path: /carrier

Current_File_System: ext4

Fstab_File_System: ext4

Backup_Method: files

/cota | /dev/block/mmcblk0p50 | Size: 55MB Used: 0MB Free: 55MB Backup Size: 0MB

Flags: Can_Be_Mounted Can_Be_Wiped IsPresent

Primary_Block_Device: /dev/block/mmcblk0p50

Display_Name: cota

Storage_Name: cota

Backup_Path: /cota

Backup_Name: cota

Backup_Display_Name: cota

Storage_Path: /cota

Current_File_System: ext4

Fstab_File_System: ext4

Backup_Method: files

/preload | /dev/block/mmcblk0p49 | Size: 280MB Used: 1MB Free: 279MB Backup Size: 1MB

Flags: Can_Be_Mounted Can_Be_Wiped IsPresent

Primary_Block_Device: /dev/block/mmcblk0p49

Display_Name: preload

Storage_Name: preload

Backup_Path: /preload

Backup_Name: preload

Backup_Display_Name: preload

Storage_Path: /preload

Current_File_System: ext4

Fstab_File_System: ext4

Backup_Method: files

/external_sd | /dev/block/mmcblk1p1 | Size: 14796MB Used: 12897MB Free: 1898MB Backup Size: 12897MB

Flags: Can_Be_Mounted Can_Be_Wiped Wipe_Available_in_GUI Removable IsPresent Is_Storage

Primary_Block_Device: /dev/block/mmcblk1p1

Alternate_Block_Device: /dev/block/mmcblk1

Display_Name: Micro SDcard

Storage_Name: Micro SDcard

Backup_Path: /external_sd

Backup_Name: external_sd

Backup_Display_Name: Micro SDcard

Storage_Path: /external_sd

Current_File_System: vfat

Fstab_File_System: vfat

Backup_Method: files

MTP_Storage_ID: 65537

/usb_otg | | Size: 0MB Used: 0MB Free: 0MB Backup Size: 0MB

Flags: Can_Be_Mounted Can_Be_Wiped Wipe_Available_in_GUI Removable Is_Storage

Primary_Block_Device: /dev/block/sda1

Alternate_Block_Device: /dev/block/sda

Display_Name: USB-OTG

Storage_Name: USB-OTG

Backup_Path: /usb_otg

Backup_Name: usb_otg

Backup_Display_Name: USB-OTG

Storage_Path: /usb_otg

Current_File_System: vfat

Fstab_File_System: vfat

Backup_Method: files

MTP_Storage_ID: 65538

Also there are files gpt_main_16g.img, gpt_main_32g.img, partition_info in the decrypted RUU firmware.

Partition Info:[0.01]

board_info board_info.bin 32 90

pg1fs none 8192 93

sbl1 sbl1.img 2048 77

devcfg none 512 120

dip none 2048 129

reserve_1 none 19902 98

mfg mfg.bin 512 115

pg2fs none 48510 91

rpm rpm.img 1024 71

tz tz.img 4096 70

hyp hyp.img 4096 78

aboot aboot.img 8192 80

tool_diag none 20480 98

sp1 none 20480 52

ddr none 64 171

wcnss wcnss.img 10240 73

rfg_0 none 2048 116

rfg_1 none 2048 116

rfg_2 rfg_2.img 2048 116

rfg_3 none 2048 116

rfg_4 none 2048 116

fsg none 3072 172

radio radio.img 120834 73

adsp adsp.img 40960 73

dsp dsp.img 32768 73

limits none 2 99

reserve_2 none 2110 98

misc misc.nb0 2048 118

modemst1 modemst1.img 3072 74

modemst2 modemst2.img 3072 75

fataldevlog none 40960 25

devlog devlog.img 61440 25

pdata none 512 35

local none 2562 51

control none 32 98

extra none 128 131

fsc none 2 173

ssd none 16 174

sensor_hub sensor_hub.img 1024 73

persist none 65536 83

sec none 128 82

rfg_8 none 2048 116

frp none 1024 114

ramdump none 20480 84

skylink none 2 131

carrier none 92160 87

battery none 20480 112

keystore none 1024 98

apppreload apppreload.img 593920 53

cota none 122880 55

mota none 2048 133

cmnlib32 cmnlib32.img 512 122

keymaster keymaster.img 512 136

devinfo none 2048 137

reserve none 8906 98

hosd hosd.img 131072 113

mdtp none 65536 130

cache none 524288 131

boot boot.img 131072 72

recovery recovery.img 131072 113

system system_raw.img 6488064 131

###LAST###

userdata none 21889024 131

but as I understand the output of brick-making command, gpt_main_32g.img was flashed while other partitions were not. So I'm not sure about correctness of it.

I put link to all mentioned files in PM.

As I understand unbricking for htc a9 much harder than oneplus, because original firmware does not include files needed for low-level flashing like various *8952*.mbn and *.xml and same files from other phones, even if you find them, could be useless because phone can accept only signed by HTC files (I'm not sure though).

Nevertheless I am ready to help testing your method.