Set the mode dropdown at the top of the Schedule tab to Online. It behaves like the on-site programme in every respect: day chips above the list, and a day, a time and a room on every card.
Every time you see is the conference’s local time. The schedule is not converted to yours — a session at 2:15 PM is 2:15 PM where the conference is, whatever your clock says.

The conference’s time zone is printed once, in the event header beside the dates. Everything in the programme is in that zone, and nothing converts to yours.
Your calendar is the only alarm you are going to get. Nothing on the platform knows what time it is where you are.

Presentations are grouped into containers — three or four papers running one after another under a session name. The joining link belongs to the container, not to the papers inside it.
This is the commonest way to be locked out of a session you are registered for: looking for a link on the presentation you marked, and finding none.

A hybrid conference runs across every time zone there is and nobody is awake for all of it. Two things outlast the live hour.
Live is the only part that expires. What was said in the room is gone; the work, and the conversation about it, are not.

There will not be. The joining link belongs to the container — the session that holds it. Click the session block in the schedule and look in Container details.
You have to work it out. Times are shown in the conference’s zone and are not converted to yours — the offset is in the event header beside the dates. Convert the sessions you have starred and put them in your own calendar.
The presentation page is still there. Every accepted contribution has digital media, it stays up permanently, and the discussion board is still open.
What is guaranteed is the presenter’s own digital media on the presentation page. Whether the live session itself is separately recorded is up to the conference.
Yes — on that presentation’s discussion board. The presenter gets a notification and an email, however long afterwards it is.
Yes. The program, the media, and the boards all sit behind a registration, and there is an Online option on the Registrations tab.