So I still believe it could solve 130 and then you would have to do some manual math (nothing hard) to get the actual private key. If the key starts with a 2, I think it would not require the manual math, but if it starts with a 3, then it will.
You can't because GPU uses only 128 bit variable to store distance on each kernel call, it means that when kangaroo jumps out of 128 bit space, all subsequent jumps are calculated incorrectly.
130 puzzle still can be solved with unmodified JLP's kangaroo if you divide 129 bit space into two 128 bits parts, but kangaroos still can jumps out, so you have to control the wrong DPs.
Are you sure? When I tested many moons ago, if I ran a higher range than 128 (b/c hash table only stores 32 hex characters for point and distance (32x4 = 128)), the distances and points were correct, but obviously the leading characters were left out/off because of the 128 bit max storage.
I may have to run again and retest, and extract the hash table....I will check it now.
Update:
It is as how I remembered it. I just ran a super quick test for the 130 bit range. As you know, the program subtracts starting range so we are working with 0 thru 1ffffff.....(129 bit range)
Here is extracted DP, DP of 20:
178559a1004e94449e90d76ca10b3600 26311140a6e43a1530526461aed458e4
On the surface, if you just plugged in 26311140a6e43a1530526461aed458e4, it seems false, but we know that the only other possible number that could be added in front is a 1, so add a 1 to 26311140a6e43a1530526461aed458e4 and you get 126311140a6e43a1530526461aed458e4, now cross reference that distance and you get this point:
0300000B71D19F5FCD4AC6184EDE7C000C178559A1004E94449E90D76CA10B3600
which matches up to:
178559a1004e94449e90d76ca10b3600
178559A1004E94449E90D76CA10B3600
So that is what I mean by doing some manual work if you use JLPs unmodded version and find a collision in the 130 bit range. But if you go up to 135, it gets a little more tricky/complicated.
But you could be correct! Maybe I didn't let the program run long enough to see how any subsequent keys would be handled.
Honestly, I wouldn't use the unmodded version, nor the 256 bit one on github (doesn't work).
To be safe, use Etayson's Kangaroo on github or mod your own version. That's the safer bet.