So I really withheld posting this because I don't think anyone would offer me a solution given the amount of people I've already asked on my own, but it's worth a shot.
I moved to NL 2 months ago for uni, and ever since I've been having this issue. What it looks like is that it shows me normal pings in the server browser, I then join the server and according to the very reliable Warband netgraph of a scoreboard I have normal ping in-game. A few seconds later that ping jumps to an extremely high value (in the hundreds, usually 200-300), and just stays around floating between that range endlessly. It's not a ping spike in the sense that it drops down to normal ping either, it's never done that. No it's not a glitch either, it actually feels like 300 ping and is impossible to play.
Okay now here's the part that makes it impossible to solve. This happens completely randomly on any server at any possible time, with no evident pattern. I also just as often simply join a server and have completely stable ping. Try that same server a couple hours later and I have the high ping issue. I've tried being in TS whilst doing this, and my ping there is completely stable so it's not a connection problem on my end. I play other games (CS, BF, War Thunder) with absolutely zero issues, never had my ping do this. However only in Warband I can go one day during prime internet usage time (say 9pm) and have completely stable ping one day, and then at 3am when nobody is even using the internet I could have 300 ping on the same server. Then the next day it's the reverse. I've asked Caskie for the 91st server IP, and when pinging it or tracerouting the results came back normal, the few times I've tested it.
I've tried verifying game cache, I've reinstalled, I've switched back and forth between Steam and non-Steam Warband, I've tried using WTFast to change my connection, I've tweaked a bunch of suggested things in my network settings based on searches, and I've reset my router countless times. The only other person who has a problem of similar calibre is Wolpi but I haven't deduced anything from it.
If anyone has any idea or if I'm simply just cucked by some shitty Turkish game, let me know