Cyclone bunk bed weight limit

We just recently picked up out first Heartland Cyclone 3010. Other than a few small teething pains the unit is just what our small family hoped for. This forum has been a huge help in answering many of our questions. We do have one concern that we addressed with our dealer and were unable to get a clear answer. The rear bunk beds appear to have a weight limit. There is a sticker on the top bunk clearly indicating a 300 lb limit. Is there anyway to modify the bunk to handle more weight? My fear is we have couples that may be traveling with us that could be close and I really don't want to carry a bathroom scale to determine who may sleep on the top bunk - Does the lower bunk have any weight limit?