almost all wodd products should be acclimated. Its not a matter of for how long. Whats important is the moisture content of the wood vs the mc of the subfloor. Ideally they should be no more than a 4% difference if I remember correctly.

Thanks, Boxer. There's no subfloor per se, it's a concrete slab. (high-rise condo) My main concern is the part by the door to the balcony - that's where you get a temperature drop, and also where the radiators are located. The existing loor (cheap parquet) warped a bit in that area. Don't know if the bamboo will do the same thing.