Hi,
I have already ask this question in the LOS16 forum a long time ago. But I am still having the same problem.
I have a Tab S3 (T825 - gts3llte). In 2018 I installed LineageOS 14.1 (Valera1978 build) without any problems. In 2019, I tried to install LineageOS 16 (also Valera1978 build), but without success. I was able to flash the ROM using TWRP and I got no error messages. Everything seemed fine. But when I tried to boot to system, I was only able to see the initial logo (the Samsung logo, not the LineageOS logo) for less than one second and then the device vibrated and the system tried to boot again and again and again.
Today, I tried to install LOS17 (also Valera1978 build - lineage-17.1-20200211-UNOFFICIAL-gts3llte). I had the same problem. The system did not boot. The strange thing is that if I install the old LOS14.1, everything works again! Am I doomed to use LOS14.1 forever...?
Summing up: LOS14.1 works, but 15.1, 16.0 and 17.1 don't. Does someone have any idea why this may be happening?
I am using TWRP 3.2.1-1_ashyx.
What I don't understand is: if I am doing something wrong, why am I able to install LOS14.1 without any problems? (I have already tried everything, wipe this, wipe that, wipe everything, formata data, nothing helps; and, again, to install LOS14.1 I just wipe the usual suspects - factory reset - and everything works...)
Thank you for your help. I really would like to upgrade my system...