Possible Clues:

• Most fresh sources of lamb welcomed by conservationists
• Most state-of-the-art
• Chimney dirt
• Up-to-the-minute
• Most recent bank getting electronic for a time
• Last to debut
• Extremely young crossword compilers comfortably ensconced?
• Music A&R guy looks for
• If we may be found in there with the eggs, you can be sure they're very fresh