If you are looking J awards, DL will seldom have good deals on it's own metal to Asia, but you can sometimes find decent deals on partners. Particularly out of west coast gateway cities of SEA, SFO, and LAX. As far as Europe, they will sometimes have decent 48-hour award flash sales for D1. These are announced around the second Tuesday of each month. In November, they had one for 98K miles roundtrip to Europe. These were seasonally restricted to flights prior to Apr 19th. Last spring/summer they had a longer running sale for D1 flights to Europe for flights from July through early September for 128K miles roundtrip. These both required roundtrip bookings (can't book one-way's for half price) and required a Saturday night stay. Also can have lengthy advance purchase requirements (the summer award sale had a 60-day advance purchase requirement).