On the "Little Bo Peep" News Flash segment (which was two parts), they had the News Flash logo on both parts. When the second part began, the music and logo was the same, but the announcer (still voiced by Jerry Nelson) said, "We take you now to the sheep meadow for an update on the Bo Peep story!"
Don't believe me? See it in action!
http://www.youtube.com/watch?v=Dp4HatIMuOY
Judging by how the Pinball Number Count is in this skit, and judging by what performers are there and the appearance of the News Flash logo, I am guessing this skit originally aired some time between 1977 and 1980. I believe the multi-part News Flashes were done in the 70s, since the Snowstorm one is from that decade, too.
Oh, and don't judge the Snowstorm skit by the Dutch version on Youtube. They just cut the News Flash logos on the dubbed versions (it'd probably be a lot of work, but they could just have a Dutch voiceover saying someing translated from "We now bring you this Sesame Street News Flash with Kermit the Frog!" in the Dutch language, of course.)