The Low Power TV stations in the U.S. do not yet have a head deadline for DTV conversion. The FCC could issue a deadline at any time. I assume that the reactions to the Friday switch will largely dictate how far out this is. Some of these stations emulate FM station on 87.7 WNYZ-LP in New York and WLFM-LP in Chicago will likely drag this out as long as possible.
3. "Nightlight" stations
To help sweep up that 2.5% about 100 stations will continue running their analog signal but only to carry DTV conversion information for consumers. I don't have a complete list but it includes: KWQC-TV, KNBC-TV, KTLA-TV, WKMG-TV, KNSD-TV, KWHY-TV, WITI-TV, and about 95 others. They are scheduled to sign off on June 26th.
To commemorate the occasion I snagged the sign offs of four Analog stations. The cut offs range from dead mid-sentence stops to 6 minute extravaganzas. Downloads below:
WBRC-TV 08:54 AM
WLNS-TV 11:56 PM
WRTV-TV 08:05 AM
WTVR-TV 08:58 PM