Thanks for that! Gave that a whirl and rebooted in normal mode, bam! Everything seemed good once again. So I restarted to check it was all okay, and it once again hit the roadblock of failing to finish booting/starting. Shut it down a few hours ago whilst I went to do some things, expecting to come back to it stuck again, but now she's booted just fine once again! Yet I haven't changed anything between the last 3 boots, with two different results.
I'm going to quickly check whether commanding a restart as opposed to shutting down and turning back on has anything to do with it..
Oh one thing to note is that on shutdown from normal mode, ever since this issue started (even when it boots correctly) it seems to freeze on the 'Shutting Down...' screen and requires holding down of the power button to finish the shutdown.