How to change drive for certain Category and its subcategories

[postcd]

Hello,

i think i better ask there than messing my torrent database.

In qbt 4.1.1 on WIndows 10 64b i have 529 torrents in certain Category (qbt can create Categories and assign torrents to them). This category has around 20 subcategories with torrents distributed in these.

The parent category has set directory as C:\CategoryName
The subcategories has either blank path (which i assume means the parent category path is used fro auotomatic management torrents or custom path is used in manual torrents) or they have path like C:\CategoryName\_SubcategoryName
The main qbt Save Path is set to E:\
Some torrents are in Automated management mode, some has custom save path
Some torrents has common files (renamed torrent payload)

My target is to move the Category and its subcategories from drive C to drive F (not previously mentioned Default Save Path - E)

How do i go about this please?

My idea (not tested!! probably will not work):

1. Selecting parent category, selecting to show all torrents, then do Ctrl + A (select/highlight all torrents) pause torrents
2. edit parent category and change save path for it (it MAY move all torrents in parent category but leave those in subcategories) - note this is probably 100K+ files and 200GB+ data on slow HDDs! Other option is to create new category and change torrents category to this new one.
3. edit subcategories one by one to update to new drive save path
4. now the torrents in manual management mode will probably still be in old drive save path and also automatic mode ones which share common files with manual management torrents
5. In qbt, click the category, show all torrents, and click column that shows current savepath (if column not there, right click some column and add it), this way i can see which torrents was not moved and remained, these i have to do manually - i think it will be not insignificant amount :-/

Any easier way? I may buy larger HDD and clone my HDD into bigger one, but i am unsure if it would work, i am using full drive encryption

How nice it could be if i can do some kind of search & replace in some qbt configuration file, see this feature request