Question about torches

Hello everyone, it's my first time posting in this subreddit and I have a question for you (I tried to search for previous posts, but the answers were so varied I figured I'd make a new one).

I've been GMing for a few years, initially 5e before diversifying to various other systems, and I've finally had a chance to run Shadowdark last week. I've run Trial of the Slime Lord for level 0 PCs and once the torch timer was near the end the players wanted to start a new torch, which as per the rulebook can either continue on the same timer or restart it if they extinguish the first one. But in the latter case, does the first torch become reusable or is it gone? I'd say yes, but I wanted to see what the opinion of others was (I trust my players to accept my ruling once I give them my reasoning, so we can establish a rule for our campaign going forward).

What do you think?