My gas supplier has changed its brands and the propane-butane mix has altered.

I am a bit confused by the instruction manual. It says that we can use LPG, butane, or butane-propane mix with maximum 30% propane, but that pure propane should be avoided as it may freeze the gas solenoid. But after the instruction manual always refers to propane and not to butane, as if the gas normally used is propane.

My supplier has pure butane, or the butane-propane mix is now 65% butane 35% propane. Is pure butane okay to use, or is a butane-propane mix better due to the lower boiling point of propane? I typically fly in temperatures from freezing to 20C. I take it the mix of 35% propane is not recommended?

Harry