The Hamanasu runs every day. As indicated at the bottom of the page on Hyperdia, it is presently current only up to September 30. If you do a search on or before September 30, the Hamanasu appears. Also, in order to go to Aomori from Tokyo, you need the Hayabusa.
EDIT: Hyperdia has been updated yesterday (September 29), and now the Hamanasu does appear with the search settings in OP plus the Hayabusa.
According to the PDF:
PDF does not mention New Year period as it shows only schedule until Nov 30th.
PDF also does not mention shorter stop in Aomori until Sep 30th. I checked current schedule and it shows 6:19 arrival today, so it seems PDF is accurate.
Credit:stackoverflow.com‘
4 Mar, 2024
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