From the ALPG 15.2:
If this session completed an AL one-shot or part of an official D&D adventure, or the adventure instructs, gain one level or decline to gain a level and keep the rewards earned.
So, if you complete an AL one-shot adventure, you can gain a level at the end of that session.
If you are playing an official WotC hardcover, then you can gain a level at the end of your session. But communicate with your DM to see if they prefer you remain at the current level.
From the ALPG 15.2:
You earn 10 downtime days.
At the end of your game session, you gain 10 Downtime Days. There is no minimum length of time for a session.
There are some adventures that are comprised of many one-hour “mini-adventures”. For example, DDAL05-01 or DDAL07-01.
Each mini-adventure counts as an AL one-shot adventure. Speak with your DM on if/how they want to split the sessions.
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DDAL10-00 Ice Road Trackers does not count as such because it describes itself (on the cover) as “An introductory adventure comprising four 1-hour episodes.”
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