3 months in IB - stay on or leave?

Serious discussion here - I joined a BB for about 3 months now on their ECM desk (First experience in IB, no SA). The bulk of my work consists of setting up calendar invites, organizing meetings, forwarding docs from legal to investors and vice versa. ECM related work at this point just consists of gathering / compiling investor feedback and helping with pitchbooks. No valuation work / deep diving into certain industries.

I don't really have a problem with the actual work, I get that at a junior level someone has to do the grunt work, and I wouldn't mind getting my salary to just do that. The issue is that I have trouble adjusting to the rough hours, the volume of numerous things to do, and not having the ability to plan my schedule anymore.

I knew that it was gonna be tough going in, but actually losing the control over my life , not being able to go out for an hour dinner on a weekday night without the fear of suddenly needing to schedule dial ins for a call to happen 1 hour later just hits different.

Not sure if other banks cultures are similar, but for me work starts at 9am and on a good day I end at 1am, on a bad day around 3-4am. I eat lunch and dinner at my desk because there's so much volume of things to process and send out. At this point, I'm not interested to lateral to a sector team as their hours are much worse.

My question is - Does it make sense to stay for a year to "gain experience" before I leave? I've been interviewing at a few places and managed to get an offer for a strategy planning role. Exit opps after 2-3 years places people at MBB / Google / other MNCs in strategy or BD type of roles. Granted, this place would cut my salary by about 25%, but from what I hear the team is great and I won't be pulling the same hours I currently do in ECM.

I'm quite certain I don't want to stay in banking in the long term as I don't think the lifestyle is sustainable for me. Just not sure if there is any value in sticking it out for 1 year, especially since I'm in ECM.

For those who need extra context and wondered why I even joined IB, I was a lateral hire and felt IB would be a stepping stone to open up other opportunities in the event I finally decide what I wanted to do. 

Appreciate some advice and yes, I understand that many people would kill to be in my position, and I am definitely thankful for the opportunity. Just that I don't think I am suited to be in this industry.