Not being able to exit Odyssey at any flux and only the final flux is very limiting and negates accomplishment achieved if unable to do so. I do understand the concept of needing to get to the last flux, but even if you run right there after the first time completed. You receive nothing. Other content allows you to retain achieved rewards Omen, Delve or in the case of Nyzul Isle you are able to exit on each and every floor if you wish. Keeping what you have achieved already, albeit every 5 floors. 100 versus 7 floors is a bit different and every 5 floors makes sense there.
I am suggesting adding a system similar to Nyzul Isle that will allow the player to exit at any flux and keep the rewards they have obtained. After activating the final flux for the first time. Nothing changes if a player times out, the player would still get nothing.
Just something that I think would make the Odyssey content a little more friendly and not be a race to get to the final flux. It's about the journey and not the destination. Do what you want in Odyssey and exit where you want after activating the final flux the first time.