Younger Than Yesterday
Release history

Date
Label
Format
Country
Catalog
Notes
February 6, 1967
Columbia
LP
US
CL 2642
Original mono release.
February 6, 1967
Columbia
LP
US
CS 9442
Original stereo release.
April 7, 1967
CBS
LP
UK
BPG 62988
Original mono release.
April 7, 1967
CBS
LP
UK
SBPG 62988
Original stereo release.
1987
Edsel
LP
UK
ED 227
-
1987
Edsel
CD
UK
EDCD 227
Original CD release.
1989
Columbia
CD
US
CK 9442
-
1993
Columbia
CD
UK
COL 468181
-
April 30, 1996
Columbia/Legacy
CD
US
CK 64848
Reissue containing six bonus tracks and a partially remixed version of the stereo album.
May 6, 1996
Columbia/Legacy
CD
UK
COL 4837082
Reissue containing six bonus tracks and a partially remixed version of the stereo album.
1999
Simply Vinyl
LP
UK
SVLP 0007
Reissue of the partially remixed stereo album.
1999
Sundazed
LP
US
LP 5060
Reissue of the partially remixed stereo album with three bonus tracks.
2003
Sony
CD
Japan
MHCP-69
Reissue containing the partially remixed stereo album and six bonus tracks in a replica LP sleeve.
2006
Sundazed
LP
US
LP 5200
Reissue of the original mono release.
March 22, 2011
Audio Fidelity
CD
US
AFZ110
Reissue of the original mono release.
May 30, 2012
Sony Music Entertainment
CD
Japan
SICP-20375
Reissue of the original mono release and the partially remixed stereo album, with three bonus tracks in a replica LP sleeve.

Question: What are the dates and catalog numbers for the US and UK releases of Younger Than Yesterday? 
Answer: Younger Than Yesterday was released on February 6, 1967 in the United States (catalogue item CL 2642 in mono, CS 9442 in stereo) and April 7, 1967 in the UK (catalogue item BPG 62988 in mono, SBPG 62988 in stereo).