  Accretion luminosity of young star FU Ori increased from undetectable levels
to hundreds of Solar luminosities in 1937 and remains nearly as high at the
present time. In a recent paper we showed how Extreme Evaporation (EE) of a
young gas giant planet that migrated to a 10 day orbit around the star may
power FU Ori. However, our model assumed a power-law mass-radius relation for
the evaporating planet. Here we employ a stellar evolution code to model mass
losing planets. We find that adiabatic planets expand rapidly, which results in
runaway FUOR bursts. Super-adiabatic planets contract while losing mass; their
outbursts are dimming with time. Long steadily declining bursts such as FU Ori
require relatively fine tuned internal planetary structure, which may be rare.
More commonly we find that super-adiabatic planets contract too rapidly and
their EE falters, leading to FUOR burst stutter. This stutter allows a single
planet to produce many short repeating bursts, which may be relevant to bursts
observed in V346 Nor, V899, V1647. We compute broad band spectra of our best
fitting scenario for FU Ori. Since the outburst is triggered behind the planet
location, the mid-IR emission rises many months before the optical, similar to
bursts in Gaia-17bpi and Gaia-18dvy. We show that in outbursts powered by the
classic thermal instability, mid-IR lags the optical, whereas the dead zone
activation models predict mid-IR light precede the optical burst by many years
to decades. We comment on the stellar flyby scenario for FU Ori.
