i changed the bg image of this map since wednesday:
http://osu.ppy.sh/s/41931
today is friday and still hasnt change. I thought i had to full submit then wait 12 hours aprox.
so, am i doing something wrong or do i have to wait more?

Tried clearing your browser cache?

Still hasnt changed..
What now?

Moar bump, seriously i need help :/

There are at least 100 of these issues in this forum, usually with solutions. Have you tried searching a bit?

Thumbnails are always finnicky. Don't worry about it, just wait.

so i have waited a bit before bumping these again.
I have been searching the forums for an answer to this issue, but none of them work to me.
besides, this is what happens now:

I have been told that this problem can be fixed by BAT and / or peppy.
So, any thoughs?

Option 1:
1) Make sure that the background file in the .osu files is all the exact same filename (if you are using just 1 background).
2) Make sure that the filename in the .osu file exactly matches the filename in the folder (ie make sure capitals are correct).
I haven't tested to see if this actually causes the background to mess up, but I assume so, since I've seen it happen before.

Option 2:
1) Make a backup copy of your whole map.
2) Delete everything in the folder except for one osu file and the audio.
3) Full submit.
4) Add in the background you want shown and full submit.
5) Go to the download page and press ctrl+f5 to skip the cache.
If it worked, proceed to full submit with the backup copy of the map now.

Option two is meaningless. Also keep in mind images are CDN cached now, and may take up to four hours to update.

um sorry for the bump, but i tried doing option two suggested by ziin. Also waited those four hours you told me about and skipped the cache. 18 hours has passed and still not updated. How much long im supposed to wait?