2.5 square feet per bird is much too small for bobs. They are too hyper and large for such a small space and would be asking for trouble. What type are the "other bobs"? Snowflakes are the least aggressive of the bob species and might not do well with other bobs. However if these have all been raised and living together for sometime, they may all do well. When the breeding season really kicks in, you may need to pair up and separate all these bobs. They belong one male to one female.
Adult Bobs require at least 4 square feet per bird. You can use this size as a grow out pen, however as they age, this space will not be sufficient and there will be aggression, fighting and possibly blood shed.