The flaw in that assumption is that you’re only counting the recrding capture time. With proper processing to clean up any noise, tidy inter-track gaps and labelling for multiple export and the exporting of the production WAV files and backing thme up - with that lot you can comfortably at least double the 30-50 minutes.
I’v’e gotten quite slick at this process I’ve converted a lot of LPs - finished all of mine a couple of years ago (but that was a 3-4 year project). Right now I’m still working on my wife’s collection - almost down the the last box, phew… (but then there’s all her tapes).
The best thing I found (from a steer from Koz, for which I am eternally grateful) fairly early on was a tool called ClickRepair which does an amazing job - it costs a litlle (US$45 these days IIRC) but is wll worth it IMHO - see this sticky thread: Click/pop removal - ClickRepair software
It’s a labour of love, enjoy it - enjoy listening to the music as you record it, have fun.
WC.
P.S. A lot of Lps have been re-issued as CDs, so if you can get a cheap-ish CD copy that’s way easier than doing the LP transcription. All you have to watch out for is that some aof the re-issues are “re-mastered” to make them sound “louder” - and this is not always an improvement.