Slow progress on this one.
After 46 days the pH of LS-1b has fallen from the initial 9 to 6.5 and it no longer works.It is falling towards the pH of sodium ascorbate and the only explanation I can think of is that free sodium ions that initially supported pH 9 may be complexed in some way and taken out of service by ascorbate.
I may try less hydroxide to make solution A, needing less ascorbic acid,and possibly adding sodium bicarbonate to give some buffering, as ascorbate/carbonate did not work.
It was in a nearly full bottle and the pH drop seems too much for the small amount of oxidation to have been the cause.