I went on a Jhourney retreat with about a year of daily practice under my belt. I didn't reach jhana, and was a bit discouraged after finding out that almost everyone else around me had! I think around 75% of those who attended based on my calculations. Including those with almost no background in meditation at all. But also some people who came to the retreat had already had access to these states. I do credit the retreat for reinvigorating my practice though, and reinforcing that jhana or no you should be aiming to be relaxed and joyful after most meditation sessions or you're probably doing it wrong.