I restrung some ukes a month ago and their pitch now is so stable, that I worry, if time soon will come to restring them again.
Many years ago I read a book about The Royal Opera Orchestra in Copenhagen. Part of their life in the old pit, which since has been enlarged, was about the inevitable pinging of the high E-strings of the primo violins, which was an unhappy thing with the then fairly small string sections.
To minimize the problem the violinists hammered nails in the pit wall towards the public, where they tied up E-strings under some tension, so that they, when an E-string pinged, could take a prestretched E-string down from the wall and mount it on their violin.
Have ukulele players tried something similar?
One might imagine a stiff board with a bridge-like block at one end with slits for the strings and notches at the far end for the knots. The other end then could have tuners to stretch the strings. Would have to be longer than the scale length of the given uke, so that the oscillating part of the string was not harmed by being bent.