Do you think that on-the-job training might be enough to bridge the gap?
Sure, you can learn on the fly - it's certainly more than I received when I started working, and I managed (I'm mostly self taught).
Technically, you can become proficient in the tools, you can get certificates, but BIM is about virtually designing and managing construction processes. That part you won't learn in front of the computer - but the same applies for any "office design" job.
To be good in "BIM", or going further, managing multiple disciplines, you need to be good in building construction (if you had BC courses at the university, you are most probably set to go) and communication - you won't know anything about a lot of fields (I assume you graduated as an architect), keep an open mind and never stop asking, be curious about anything that crosses your path.
I would start practicing communication with your prospective office: share your doubts with them. I think no one sane will ask you to do things or put responsibility on your shoulders that you wouldn't be able to bear. But not applying pressure also means you won't have external factors that require you to develop. Don't take on too much pressure, that will break you and you will experience burnout sooner than later.
It's a delicate game, start playing! Good luck!
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