I talk to Frank all the time, sent him an email late last night & got a reply an hour ago, but we have been friends for several yrs now.
Last wkend was a big model construction show in Friedrichshaven, Germany which he attended setting up his own booth. Fumotec is a one man business & Frank still maintains a full time job with Vario Helicopters too.
Sometimes I get next day replies, sometimes it's 2wks later... depends on the timing as there's many model fairs that are frequent throughout the yr in his immediate area.
Be patient, he'll get back to ya. I'm sure he gets a lot spam & just general email of semi-interested inquiries to weed through every week.