I calculate that Wabtec will need to deliver 1.85 sets per week, every week from now until the end of year to enable them to complete the delivery programme by the end of 2019..
Would anyone put a bet on that?
The refurbished set situation should improve shortly - Set 3 is due to be released imminently, with sets 4-7 to follow. Sets 8 & 9 have entered Wabtec. Not ideal, but should enable the use of 'Classic' sets to be reduced in the near future. Hopefully, the experience gained with the work to date will speed things up for the rest of the coaches.
The situation to date has been, quite frankly, unacceptable - but both Scotrail & Wabtec have been pretty definite that all the refurbished sets will be completed this year. That's a tall order, but one that does seem to be taken seriously now (see Wabtec having a recruitment drive for the Kilmarnock site).
Scotrail seem to be pretty clear about this (for once). That's a definite, clear target, which (as I'm sure Scotrail will know, will come back to haunt them if it isn't met) Scotrail must be reasonably confident that this will happen. Therefore, I'll hold off on the negativity unless THIS target isn't met!
We will have to wait and see. Personally, I can't wait to see a refurbished set 'in the flesh' - it will get rid of the major issues of station dwell times & retention tanks which wreck the timings of the 'Classic' sets & offer the passengers a huge upgrade in the whole travel experience.