I wish that we stop using the term "fresh flash". There is no such things as "sour flash".
When you flash/install an image, nothing is kept from the old image. It does not matter whether you use Image Manager or USB method to flash the image. (If you flash a backed up image, it will be an exact copy of the backup image.)
After you flash/install an image, if the first install wizard finds a settings backup on the connected storage device, it will offer you the option to perform a restore. When you restore settings, that is when you restore/transfer the old settings.
We previously suggested that after flashing/installing a new image, do not restore anything. However, it has transpired that this is not necessary. A "settings" restore is generally fine.
In conclusion, when it is suggested to "fresh flash", what is meant is:
Do not perform an online update! Flash the image using USB method or Image Manager. Do not restore settings or plugins.
In my opinion, it is far better to say "Flash new image, do not restore anything".
Recordings:
The image is installed onto the flash memory. Recordings are made to the Hard Disk Drive. Flashing a different image will not affect the recordings. Some people mistakenly think that they have to initialise the HDD after installing/flashing an image. This formats the HDD and all data on that device is deleted.
