Questions before reflash an XA2

[mips_tux]

Hello Sailors
My X10ii is now up and running with Sailfish OS

Now I would like to give my wife my XA2 to replace her Intex Aquafish.

I want to get back on good bases and reflash my xa2. My questions may be silly, but I don’t want to be wrong If I look at the instructions of Installing Sailfish X on XA2 using Linux - Jolla :

1/ no need to unlock the phone, it is already since it is under Sailfish OS but for me as previous,

2/ in the same folder - I extract this zip file: Sailfish_OS-Jolla-4.2.0.21-h3113-0.0.8.7 that my wife bought and downloaded yesterday and I extract this zip file: SW_binaries_for_Xperia_Android_8.1.6.4_r1_v16_nile.zip

Now it seemed to me that Sailfish OS 4.1 then 4.2 came with an update for Android in version 10. Now I understand that it remains in version 8 for reflash. Will the update be done when the phone xa2 reflash?

I’m quite sure that this process is good, but fhank you very much for your help and that i don’t make mistakes

Precision : i used an PC under Debian 11

[jameson]

There are two “Androids” in SailfishOS phones. One is the hardware abstraction layer, including drivers to allow the OS to operate the hardware, and this is the one you flash before first install of SailfishOS. The Linux kernel running SFOS uses this Android HAL in order to access the device hardware The other one (optional) is the Android compatibility layer, and this one runs on top of the Linux kernel; this is the one SFOS uses to fool Android apps into believing they are running on Android. These two “Androids” do not need to be the same; the latter one may be (and usually is) updated together with SFOS.

[mips_tux]

Ok, thanks for your answer. It seems very clear.

[peterleinchen]

But why do you want to flash at all?
Just reset the device and update and configure and it…

[mips_tux]

By paying a new license, it’s a way to support Jolla. And say that we are happy with this OS.
And make all the update since version 3.0+, it’s quite too long

[wetab73]

I’m going to reflash my XA2 Ultra in order to possibly get rid of some issues as reported in other threads. I flashed SFOS on top of Lineage 18.1 (i.e. Android 11) without downgrading it to Sony’s stock Android, and maybe that’s what causing some issues, so this time I would like to do it strictly as it should be. So the question is:

in Emma tool both Android 8 (the one the XA2 Ultra originally shipped with) and Android 9 (then released as an update) are available for XA2 Ultra. So, before reflashing back to SFOS, should I flash Android 9 right away, or Android 8 and then upgrade it to 9, or just Android 8 and then SFOS, without ever upgrading to Android 9? In other words, which Android version is the best and least problematic “base” for SFOS on XA2 Ultra Dual Sim?