Thanks Mike! I started by reading the series, but now I'm trying to follow along and actually do all the steps. I believe the expired URL is from Stairway 3, where it linked to where you originally got the files from. Other stairways in the series do link directly to your zip file which works.
I'm running into another problem... in stairway 6 about 1/3 way in the code references a file /ssc_uk_postcodes/postcodes/postcodes.csv. It doesn't seem we've actually created this file. I thought that maybe this should be the file NSPL_MAY_2016.csv however the schema doesn't match. I've looked again at the previous parts of the series and I don't see any references to this file. Have I missed something?