If there is an operating system update (compare with Windows7 => Windows8) you need to flash. Such a change happened a few days ago.
Theoretically you can update, but you'll have to download over 300 packages (which overloads our download servers), and there is a big chance that you'll have problems (for example if the network package updates, you loose network connection, causing the rest of the update to fail).
So for most users, flashing is a lot easier, done in 5 minutes, and if you have the autobackup plugin active, even without loosing any settings.
Currently in use: VU+ Duo 4K (2xFBC S2), VU+ Solo 4K (1xFBC S2), uClan Usytm 4K Ultimate (S2+T2), Octagon SF8008 (S2+T2), Zgemma H9.2H (S2+T2)
Due to my bad health, I will not be very active at times and may be slow to respond. I will not read the forum or PM on a regular basis.
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