Samsung S9 starlte upgrade from Q to T


If I use the upgrade instructions here to go from Q to T, (adb sideload the .zip and reboot), am I going to lose apps and data? I feel like I should know the answer to this question but hey, it’s been a while.

Hmm. On further investigation it seems I have to install stock S before upgrading to T. Or at least that’s what I think it says. Anyone else succeeded in upgrading their Samsung ?

I think this is a duplicate question to this one.

I don’t think so. For the Samsung S9 the last stock ROM is on Q.

I post you below a conversation with @piero and some question that I have.

Hi piero,

Sorry to bother you but I’d like to have your opinion on how to proceed to switch from android Q to T on a samsung galaxy S9 (SM-G960F) with at the time of writing the following version on it:
1.14-q-20230816320942-dev-starlte. Several things confuse me in the different information I’ve been able to find on the forum

Here’s how I see things:

  • Make a backup of my data (that should do it)*
  • I was going to install version 1.15-q-dev via OTA initially.*
  • It says for some devices that you have to go back to stock ROM but I don’t think that’s necessary for the S9, especially as I’ve read this: Some of the devices which require firmware partitions to be installed will get the firmware partitions included in the recovery zip file. So with version 1.15-q-dev I should have the latest recovery, i.e. e-recovery 1.15.*
  • I’m thinking of downloading /e/OS build: T dev here: and saving it directly to my phone.*
  • This is where I don’t understand, on the page it talks about using adb on a PC, but isn’t it possible to proceed directly with e-recovery without using a PC? If so, I can’t find a procedure apart from here, but it’s vague: [HOWTO] use e-Recovery to wipe & format data before sideloading/installing eOS*

What do you advise me to do, go through ADB with PC or use e-recovery (knowing that I don’t really know how to do it, it’s not as detailed as TWRP in terms of how to proceed)?

Thanks for your help ++++


Piero answer:


The latest version released by Samsung seems to be HFVG4 1(August-2022) which you should already have installed (check, baseband version in settings, about…) so I don’t think you need to go through the stock ROM again.
Yes, you can bypass the PC and ADB by using e-recovery (illustrations in [HOWTO] an Unified Install Guide Project for /e/ - #4 by piero).
First try simply flashing the e-1.15-t without wiping or formatting (you can use the e-1.15-q if you like).
When you upgrade to a higher version of Android, formatting the /data partition is sometimes necessary because it’s not organised in the same way.
This isn’t necessarily the case today when going from Q->T (I’ve been absent from the forum since the release of T).

@nickd all those cautions are “generic” unfortunately. You need a certain knowledge of the latest firmware for the device.

I suggest that you take the baseband quoted as from @piero as correct. If you have that you will be much more certain that you already have the requirement “latest manufacturer firmware”.

That’s really useful, thank you.

However, I am on baseband HFVB4 not G4. I don’t know what difference that’s going to make.

B is for february
G is for july

Currently I’m on 1.15-1-20230914331056-dev-starlte and planning to upgrade to 1.18 but also have baseband version HFVB4 instead of the latest G. Is it needed to first install the original stock Samsung ROM to get the latest baseband or should it be ok to proceed using the current baseband version.

I wish I knew. I let it drop in the end because I’m travelling a lot at the moment and couldn’t take the risk upgrading my 'phone.

I was going to change from Q to T like you did with my S9 but I’ve given up for the moment. Too much uncertainty about what to do and, above all, the sheer laziness of having to make a full backup of my data first.
Honestly, I’d say you don’t need to go through the stock ROM again, from what I understand.
If I ever do the upgrade I’ll post on how to do it.

HFVG4 firmware have the same modem related partions (CP) as HFVB4,
only bootloader related partitions (BL) and android system related partitions (AP) have been updated in HFVG4

Example XEF France (carrier free) :

Some rare country / carrier have more recent builds :

But also with the same HFVB4 baseband version (CP)

Example MID Irak :

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Thanks for the info but what is the answer to the question - is it possible to install T from the HFVB4 baseband version ?

Of course yes… But coming from /e/OS-Q, you probably need to wipe or format /data partition

Just to share my experience.
I’ve followed the upgrade instructions but indeed got into the bootloop as also mentioned here. So I guess piero is right and a complete wipe or format/data is needed. I guess in e-recovery this is done with the factory reset option, right?
For now I’ve just used e-recovery to get the device in sideload mode again and restored 0.15-Q. That got my device working again.
One question remain though. In the upgrade instructions links to the latest e-recovery are provided but they’re not used in the instructions. I haven’t used those latest recovery since I guess that’s not needed. Is that correct?

you also could download the file directly on the phone and apply the installation localy from the recovery mode (without computer)

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In addition to the file-manager of your computer to copy/past on it the device internal storage (where your photos and other documents are.
You will probably need to install TWRP on the device to backup your things (apps and personnalisations are on the /data partition)

, or another backup solution

A quick update just to confirm that (of course) piero was right about the baseband version. I’ve finally upgraded from Q to R stable with baseband version HFVB4 and everything seems to work as expected.