3 bath E-6 working solution life

[bottlegardener]

Hi all,
I hope this hasn't been discussed to death (I don't know the lingo well enough to do a proper search)...
but I'm hoping to do my first E-6 home processing today and I was wondering if anyone had an idea about the life expectancy of a mixed working solution?
My Unicolor 1 quart kit (which I believe is also sold by Arista) is a bit ambiguous on this topic.

MORE CHEMISTRY CAPACITY

One is always concerned about chemistry life and capacity, quality of results and economy when processing multiple rolls in a batch of chemistry. From the user’s viewpoint it may often seem that chemistry manufacturers are somewhat arbitrary about the number of films which can be processed before the chemistry must be discarded. This stems from the manufacturer not knowing - only guessing - four essential things: how many films will be processed in freshly mixed chemistry; in what manner and how long will the chemistry be stored before processing again; what contaminants have entered the system from either the water supply or from unintentional chemical intermixing; and how far can the results deviate from ideal before the user deems them unacceptable. If you will recognize at the outset that all developer start on an inexorable downhill exhaustion path the moment they are mixed, and exhaust faster in the presence of air, contaminants and
high temperature, and suffer superimposed stepwise exhaustion with each use. We can offer some observations on extended chemical capacity:
• If you accept the role as the final arbiter of acceptable results it is easily possible to process 25%, 50%, or even more rolls of film than those listed in the capacity charts, so long as all processing takes place within several days after mixing the chemicals. There is only one rule in this exercise: process film until you no longer like the results. The safeguard in this procedure is that results generally will not plummet precipitously from “good” to “bad”, but will change gradually.
• If you again take full responsibility for quality of results, it is possible to process more film over a much longer timespan. This procedure is somewhat risky unless you process some film every day or so to monitor chemistry performance. Otherwise, partially used working solutions left untouched for a week or more might have changed so significantly that you would suffer a dramatic decline in results. If you choose to operate under these conditions, our best advice would be to process a small piece of test film, and on the basis of these results, decide whether or not to commit valuable pictures to the chemistry​

In my case, my hand processing tank has a 20oz capacity (which is equal to 0.625 quarts) and I hope to process 4 rolls (Ektrachrome 64 tungsten balanced - expired 2007); judge if my exposure was OK (I metered for iso on the tin) and adjust if need be and shoot four more rolls and process them maybe four days later.
I'm ok with even extreme colour shifts but I'm not a fan of blotchy grain or really dark murky slides.
Does this seem do-able?

 

[thuggins]

My Tetenal mixes have lasted five weeks.

 

[Rudeofus]

The most critical component is first developer (FD), and this one will not fail all of a sudden, but slowly and incrementally. Over time the FD will yield darker and darker slides until the effect becomes too obvious to ignore. When this effect will become obvious depends on subject matter, your exposure consistency, oxygen permeability of the container, ambient temperature, age of the FD concentrate, and 1-2 weeks are typical time frames in which FD will likely give good results. You may compensate aged FD with longer FD times, but colors may still be off.

 

[bottlegardener]

Thanks for the info folks! I'll be watching for the these defects to manifest themselves.
It's been about three weeks since the initial working solution mix. I've processed 10 rolls worth (I have an expired bulk roll) and everything still seems to be working well.
My two rolls were quite poor (they looked like very old faded slides), *I think* because allowed the colour developer and blix to cool down a few degrees and I failed to compensate with longer times. After that, I got a bit more careful about the temperature and also left the film in the colour dev and blix a tad longer; I've been pleased with the results.
Also, I got an inexpensive, fast-reacting dial thermometer after the ill-fated first two rolls. It's been a very useful tool.