(09 May 2016, 6:06 pm)NK53 TKT wrote Amazing scenery on the Newcastle-Carlisle train, I recommend you get the 10:22 train because it is Abellio Scotrail, this is better than Northern

In your opinion
Bearing in mind the Scotrail operated services continue to Glasgow; this often attracts a different range of clientéle as opposed to Carlisle services - usually more tipsy and loud from past experiences.

(09 May 2016, 6:19 pm)Andreos1 wrote No idea which runs are scheduled to be 156's. Fingers crossed you don't get a 142! I have been fortunate enough to have never had the latter on the Tyne Valley line. If you are looking to go in to the lakes, the rover that includes bus, ferry and train might be worth looking at.

No 'booked' daytime diagrams as such for 156s or 142s on the Tyne Valley.
Some people like 142s...

(09 May 2016, 6:59 pm)Jimmi wrote the withdrawal of the evening 42's between Blackpool and Lanchester.

That's a route and a half that Jimmi! :p

(09 May 2016, 7:50 pm)Dan wrote Andreos mentioned it a few weeks ago and I posted the link to it - but can't find it now.

Lakes Day Ranger:
http://www.nationalrail.co.uk/times_fare...c4cf1.aspx

Various day rangers around the lakes. Cumbria Day Ranger covers you Carlisle to Preston via WCML and via the Cumbrian Coast as well as Northern's Oxenholme - Windermere services too.
I'd recommend having a look through the Northern 'special offers' page (same link as Dan earlier but this shows all products).
http://www.nationalrail.co.uk/times_fares/1418.aspx

On a slightly biased note, if anyone gets the chance to go on the Cumbrian Coast, Mon-Sat you can join a Class 37-hauled service with Mk2 coaches. I personally would really recommend it.  
 

Re your earlier question about advance fares; Northern did have very good advances (such as Carlisle to Newcastle for £3) up until the Tyne Valley shut with the Farnley Landslide. They've weirdly never came back which is a big shame.
So no, the ticket you buy on the day will be the one.
Do you happen to have a railcard (I'm guessing you're over 16)? 16-25 costs £30 for a year and saves 33% off tickets with various peak time restrictions. http://www.16-25railcard.co.uk/