Sorry for the delayed reply @oddity, Sundays are my official "UnDays"
Please feel free to shoot me a PM when you have a chance and I will help you address whatever issue this may be.
I've logged in to your server via PM communication and the following is a result.
Syncthing is normally updated via the GUI, however with some of their recent updates I have noticed them requesting the application be updated through apt. It's safe and advisable to constantly keep your systems up-to-date with the latest security releases and there should be no ill effects to QuickBox or any of it's processes in doing so.
Through ssh I rant
apt -y update. This will show how many packages are available, at which point you can type
apt list --upgradable to see which packages those are. If Syncthing has an update candidate, you will likely see something similar to the following:
Now you can upgrade Syncthing simply by typing
apt -y upgrade.