now my is stable up to 252 bit. and yours? Ps. of course you have script, becouse it is math, the problem is with precision , and it depends form kind of algo you will use, sometimes must be somethng changing, but you have not ansered, what kind algo? if you don;t know then you have use one of google scipt.
my task:)
Did you write something about algorithm in your own script? Why I have to uncover my mathematical poetry?

But ok, this is not secret - algorithm is well known lattice reduction, as was already mentioned on this forum. It works perfectly with only 4 known bits of nonces (yes, up to 252 bit nonces) and any private key length. I don't know why you also required reduced private keys.
Also I don't understand what a problem you mentioned with different nonce sizes. If all of nonces is beetween 2**1 and 2**240 then it is obviously that we know that at least first 16 bits are zeroes - this is enough for construct the matrices, and other 240 bits do not matter whether there are zeros or not.
This code is very close to my own.
@_Counselor
Sorry for late with an answer, but had other things to do.
So: the question :
I don't know why you also required reduced private keys.becouse standard lattice work as well only and only then when nonces are 1 to 2**n bit , but what when you have curve.n-2**n bit with 2**n bit together?
example below:
a=random.randrange(2**245,2**246)
1 ,2 ,3 ,4 - are in range as above
but neg -> means curve.n-a
and if you have nonces as a and as neg a together in your lattice -> then it will not work. but my work. this is my improvment but of course there is problem becouse my script reduces then maximum privateky I mean maximum privatekey at the moment is 2**254 or curve.n-2**254 and I'm still working with it.
and I not use implement other "scripts" all my codes I have write myself. I'm not scriptkiddy like other people here:)
here bits for 2**245,2**246 and neg is curve.n - this range.
1 60874947060654646988932696475964426048801607269300912828201839735978640501
1 0000000000100010011101000011100101000111110101011000000000110100111110111100010110000011000100111111110000100011100010111110001011011101011110011000100101001111110001100001010011000010111101100111011110101001001001010101011001011010000000001100010001110101
neg 1 115731214290255540776582052312211943426788762671805603469776961301782182853836
neg 1 1111111111011101100010111100011010111000001010100111111111001011000001000011101001111100111011000000001111011100011101000001101111011101001101010101001110010110111010010011001111011101010001010100100000101001001110010011011001110110001101010111110011001100
2 75644098440038437762652047354698002664339046624299640543507819731454403317
2 0000000000101010110100000010001110001101010011011110011100100010101011100101110000101001011100000100011000001100100110001110111100111010110001001011111011001010110011010010101101111100100101111110001111101001011110111110110110010111011000100010001011110101
neg 2 115716445138876156985808332961333209850173225232450604742061655321786707091020
neg 2 1111111111010101001011111101110001110010101100100001100011011101010100011010001111010110100011111011100111110011011001110000111101111111111010100001111000011011111000100001110100100011101000111101101111101000111000101001111100111000110101000001111001001100
3 79786659070083452362511326530490422585998946696656655231568386882005269476
3 0000000000101101001010000101101110101010011010000110011011000001011110001110111101100111011100000101101010010001110100101100011110111111101101110010000111000000110011101100101100000001110010111001111001001100010111111110110000001011100001100111101111100100
neg 3 115712302578246111971208473682157417430251565332378247727373594754636156224861
neg 3 1111111111010010110101111010010001010101100101111001100100111110100001110001000010011000100011111010010101101110001011010011011011111010111101111011101100100101111000000111110110011110011100000010000110000101111111101010000011000100101011111100010101011101