Cipher Challenge
My first Patristocrat
This is a Patristocrat: it uses one consistent cipher-to-plain substitution, but it removes all original spaces and punctuation. Ignore the displayed groups of five; they are not words. Make the first guess from a repeated sequence or a frequent letter with useful neighbors, and test a common English fragment across every occurrence, including across group boundaries. Record the tentative mappings in Hypothesis and apply them to the entire stream with Simple substitution. Add word boundaries only when several adjacent fragments support the same grammatical reading. If a boundary or mapping creates contradictions elsewhere, remove it. Continue until one-to-one mappings and the continuous English text agree, then submit the recovered letters; added spacing does not affect verification.
Ciphertext
XBDLB IDYUJ NOVND QZNBE DVNEB OLNFU EQOFU DNUJN VZBYU IYQYN UDDIO NUKZN DUVCT UXBDU ABBMQ YWXBD ZNDIE NIDUN FUODQ YNUKT ABEMZ BXXQG UVDUO DUZUY NVNQB YBYAL ZBVIZ UXIAS BDKBD DUOUV NUKZU HIUYE UCVLE DBZZV YLTAB EMTBI YKVDL TUWQY SQNFW ABTVA AUNNU DXDUH IUYEQ UZVYK DUEID DQYWN FDUUB DXBID AUNNU DZNDQ YWZNU ZNEBC CBYXD VWCUY NZZIE FVZNF UQYWN QBYVY KEBCC BYKBI TAUKA UNNUD ZBYAL SFUYN FUQDZ LCTBA OVNNU DYZXQ NVOOA LUVEF ODBOB ZUKCV OOQYW UGUDL SFUDU VYKUJ VCQYU VSQKU SQYKB SVDBI YKUGU DLBEE IDDUY EUNDU VNZOV EUZVZ ZUOVD VNUFL OBNFU ZUZCB GUBDD UCBGU NFUCS FUYUG UDYUQ WFTBD QYWAU NNUDZ ODBKI EUVZN DBYWU DWDVC CVNQE VADUV KQYWK BYBNI ZUNFU ODQYN UKTAB EMZVZ SBDKO VNNUD YZABY WUDDU OUVNU KZNDQ YWZVD UZNDB YWUDU GQKUY EUNFV YQZBA VNUKE BCCBY AUNNU DZCVQ YNVQY NFUZV CUBYU NBBYU ZITZN QNINQ BYDIA UZIZU KXBDV YLCBY BVAOF VTUNQ EEQOF UDVYK DURUE NVWIU ZZNFV NXBDE UZKIO AQEVN UOAVQ YNUJN VZZQW YCUYN ZYUVD NFUUY KIZUO DUXQJ UZZIX XQJUZ VYKZU YNUYE UDFLN FCNBO AVEUT BIYKV DQUZG UDQXL NFUEB YNQYI BIZAU NNUDZ UHIUY EUXQD ZNEVO QNVAQ PVNQB YZOVE UZVYK OIYEN IVNQB YEVYT UDUZN BDUKV XNUDS VDK