Working with a 1% BA, 5% BB, 5% PEG-400, cottonseed oil matrix one could definitely make 25 mg / mL without it crashing. I would rather have a low concentration oil prep that can be heat sterilized rather than a water one that is finicky.
If you try 50 mg/mL you are on your own as I have no direct experience working that high with that recipe. You may consider increasing the BB and PEG to appropriate levels but will also thicken the prep considerably. Maybe 1% BA, 10% BB, 10% PEG-400 to start...but that may need to be adjusted.