I don't know if
this has already been posted, but it features some pre-deregulation timetables for these services. The 212/3/4/5 look fairly familar from then to what I recall.
While the X40 was quick to Durham, it was very slow before Peterlee. It started going down from the Village, via Oak Road to the colliery, then through Horden. It took longer to get to Peterlee than from there to Durham. Indeed, the current 22 is probably faster from Easington to Durham, although the recently curtailed 65 was faster still. I don't know at what point the direct Easington to Durham service was cut - I don't remember it - but I'd imagine it was a lot better. It always felt odd that Easington - where the local council was based - didn't have a direct bus to the County town.
Wasn't there a time when either the 241 or 242 didn't serve Peterlee, but actually ran Durham to Hartlepool via Wingate? 241 I think... I believe that's where the 243 came in, as the bus ran Easington to Durham as the X40, Durham to Hartlepool as the 241 and then Hartlepool to Easington as the 243. That would have been early to mid 90's at a guess - I left for uni in 94 and for good (other than occasional visits) in 97, but I travelled daily on the X40 to 6th form in Durham from 92 to 94. I have a feeling the 242 was extended to Easington in the evenings and on Sundays, meaning if we stayed back for any reason it was a very long trip home.
I can't recall the dates of this, but there was a time when Peterlee ran 'breadvans' around the estates, with the longer distance services sticking to the main roads. I don't think this lasted long, and longer distance services ended up being diverted with the inevitable increase in journey times. An early understanding of bus workings came when I realised that if I saw a minibus on the X40 going the opposite way in the morning then I needed to make sure I got the evening return from North Road rather than Millburngate if I wanted a seat!
There were other oddities such as the short lived 23X which ran as per the 230 from Hartlepool to Easington Village then up to the A19 to Ryhope. For a time where was also a summer X98 or X99 - can't remember - which was something random like Metrocentre to Whitby which was somehow routed via Easington.
I can't quickly find anywhere that shows population over a longer period, but Easington has been pretty stable for the last 25 years and indeed projections are showing a small rise. If anything, the council policies of bringing in people no-one else wants would surely mean more demand for buses - being such a deprived area, car ownership is low - but I guess also travelling patterns will be different. Most low paid jobs will be focused on Peterlee and days out and shopping trips will be massively different to what they were 30+ years ago.