1100 is tuned for RON95, no low-octane EFI mapping available as on 1150.
And it worked OK in Iran, with around 80 ocan petrol, leaded (red colored fuel)
I've heard the same about 1150GSes that "eat" low octane fuel well in stock EFI mapping. Also you're very probably only running low octane on temporarely occasions, too.
I'd say not a thing to worry about. Carry on
Just carry a spare fuel filter with you and best if you route the fuel filter outside the tank (much easier to replace the filter) - bad quality fuel clogging your fuel filter is a bigger problem than a "working" low octane fuel.