These could be the last changes ever for The WB...

With the merger between the WB and UPN set for fall, it’s suddenly become a lot more dicey for even established shows hoping to make the fall schedule. Now come two midseason replacements on the WB also looking to make the lineup, which looks pretty difficult. The WB will add Rebecca Romijn’s dramedy “Pepper Dennis,” about a TV news reporter, to the Tuesday schedule starting March 22. It will air at 9 p.m. behind “Gilmore Girls,” pushing “Supernatural” to Thursdays at 9 p.m. behind “Smallville” in a possible preview of the CW’s new schedule. On April 4, the Matthew Modine drama “Bedford Diaries” debuts at 9 p.m. out of “One Tree Hill,” replacing reruns of “Related.” Also on the WB, “Everwood” will return to its old post-“7th Heaven” Monday spot in March, airing a two-hour episode on March 20 and then taking over the 9 p.m. slot.