I have just corrected myself, it is when the bolter completes its Bolting while you are clicking on a new heading to bolt.
The bolting as well as the backfill bugs have been fixed! As well as many other small bugs (hopefully I didn't introduce new ones!)
As soon as I'm back home from my FIFO schedule (1 week left) I'll start working on a Saving feature. This is a must indeed.
Oh and I've started working on a Discord channel, it will be launched tomorrow :)