Hello @deepee
For my part, with my S7 SM-G930F, when I switched to the Q stable version I did it without going through the stock ROM again. This information is really not precise and I can’t tell you more. On my phone TWRP was already installed, I downloaded the Q stable V1.0, be careful you have to go through the 1.0 otherwise it falls in error. Because of this I was a little confused because I tried to install the 1.2 directly and I did not understand why it crashed.
I followed the information in this link: [HOWTO] Installer /e/ sur un smartphone Samsung avec Windows facilement and went directly to paragraph 8.
For information, before doing all these manipulations, I deactivate the lock of my screen and my sim card.
I reactivate them when e is installed and working.
Once installed, the next update melts without problem. Currently I am in 1.3-q stable.
Good luck
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