Before completing “A Friend in Needle” -the first step of the Tools of the Trade quest for tailoring - my newly copied character had over 1.5 k of Tidespray Linen, including seven full stacks in the Reagent Bank and about 150 in inventory.
After completing the first step, which asks for 15 Tidespray Linen (and some other cloth) he has zero Tidespray Linen left. All the stacks in the Reagent bank are gone, leaving empty slots, as is the stack in inventory. All gone.
I did not submit a bug report with the quest as I did not notice the cloth was missing until later.
Edit: Tested again with a fresh copy of the character. The quest consumes all Tidespray Linen AND all Deep Sea Satin. (Added name of quest)