Especially if you have a rig that calls itself Dual Fuel, it would seem that you should be able to convert. I looked up a manual for the Classic 110
Page 23 of the PDF (19 of the manual pages) specifically talks about there being conversion kits to swtich to different fuels. It also underscores that this should only be done by a certified gas engineer.
That said, my experience from shopping appliances for our house remodel several years back was that some sales people just stared blankly when we asked about running stoves on propane (we're a bit out in the sticks, no Natural gas hookups). Others would look at the same equipment and say 'oh, you need the converter fixture, which was more or less a flow restrictor to keep the energy content about the same as for the NG (propane is a bit higher energy content than NG).
In short, you should be able to convert between fuels, and the manual from the company itself says so.