Today we had our first overrun. It's slippy out there.
(rather than any other contaminants such as drizzle)
As to "low adhesion" vs "leaf-fall" Whilst Slippy Season is synonymonus with leaf-fall; but, there is much more to it. This time of year you get that morning dew settling on the rails and that also causes trains to slip. The RHTT does a great job of cleaning the railhead. I would like to see more RHTTs out all year round.
All I have seen is a very few leaves on the ground (where the rails are). Of course, after a storm, leaves can come down at any time, even in, say, July.
It also takes a very minimal ammount of "leaf mulch" to contaminate the railhead. They have been dropping for some time now. That combined with the seasonal dew makes it very slippery out there. As the weather changes it becomes more important to maintain the RHTT circuits. This time of the year they are typically just water jetting and hitting the "known areas or low railhead adhesion" I don't believe they do full circuits as yet. To judge the leaf-fall I look directly out the front of my cab window. I can see the leaves dropping and I can see the contamination on the railhead. Many routes are surrounded on both sides with trees and in deep cuttings. The track is covered with early leaf-fall.
TBH the earlier the better. What I find frustrating is that the "season" is declared started/finished on a specific date. As I said earlier, its been slipping for a couple of weeks now and will absolutly still be slipping when they declare it all over.
Overall what is important is what is happening on the ground. Irrespective of the perception of it being early or late; the railway needs to be more proactive. Todays overrun could have been prevented and the early slips can be put down to complacency or sheer unpreparedness. Nobody thinks about overruns until the seasonal brief comes out or the RHTT trains start running. Even if by running them a few weeks earlier and Driver awareness is increased; that is a benefit.