Oh dear, I guess you have cracked the two caesar cryptos...
This one is more difficult. Although a simple substitution is easily cracked...
Again the characters are limited to A-Z... But I think I can come up with a 256 version again.

Enjoy!

LY WXH NCGTAXWY AES YEQ DNJ PHNS WXTR GY UPTHJS T NG TGBPHRRHS MHPY KHCC SEJH YEQP RECQWTEJ IHY TR JPPNPALLPELX WXTR CTWWCH DXNCCHJAH KNR JEW WEE XNPS KNR TW