My guess is that WGBH-89.7 will probably fill the evening (and maybe overnight hours) with:
(1) A rebroadcast of the soundtrack of WGBH-2's "Greater Boston";
(2) Rebroadcasts of the WGBH/BBC "The World" in mid-evening, and a late-evening rebroadcast of the audio portion of the "PBS Newshour",
(3) WGBH picking-up CBC Radio's "As It Happens" and "Q", and,
(4) If the syndicated (by NPR??) overnight jazz show is also eliminated, rebroadcasts of WGBH's Emily Rooney and Callie Crossley shows from the previous day, with perhaps another rebroadcast of "The World" or the previous day's "All Things Considered".
It's no secret that most NPR member stations are eliminating music programming to go 24/7 news and information. They're doing so for one basic reason:
News and information programming brings in big pledge $ to NPR member stations. Music programing generally does not.
That's why statewide public radio networks in New Hampshire and Connecticut have gone 24/7 news and information, and why I think Maine's statewide public radio network will probably do so very soon.
By the way, Vermont Public Radio a few years back wanted to eliminate music programming to go 24/7 news and information. However, VPR decided to launch a 24/7 classical-music network and once that network reached the great majority of Vermont residents (October 1, 2007), classical music was eliminated from VPR.
At the moment, VPR still airs a two-hour nightly jazz block (three hours on Fridays), but as it's host, George Thomas, has announced he's stepping down at month's end, VPR is almost certain to eliminate jazz and expand public radio news/information programming to the 9-11 P.M. period (9-Midnight on Fridays), the last portion of VPR's weekday scehdule that hasn't been converted to news and information.