Outline for the owner to write over. Background facts below are from Future Motion's support pages and the CPSC; the riding experience is his to add.
What the board is telling you
Future Motion describes two warnings. Pushback lifts the nose when you reach the top speed for your ride mode, and lifts it harder for low battery or an error. Haptic Buzz pulses at top speed, goes solid if you keep accelerating, fires on steep climbs or hard acceleration, and double-buzzes for low battery or an error. See the safety page for the sources.
What it feels like underfoot
[Describe pushback the first time you noticed it. Was it obvious or easy to miss? Same for the buzz.]
Where it shows up on my rides
[Hills, headwinds, low battery at the end of a loop. Which ride mode you use and how close to the limit you usually run.]
What I changed
[Ride mode, tire pressure, speed habits, charging before longer rides.]