  We present a continuing study of a sample 44 molecular outflows, observed in
13CO lines, closely associated with 6.7GHz methanol masers, hence called
Methanol Maser Associated Outflows (MMAOs). We compare MMAO properties with
those of outflows from other surveys in the literature. In general, MMAOs
follow similar trends, but show a deficit in number at low masses and momenta,
with a corresponding higher fraction at the high end of the distributions. A
similar trend is seen for the dynamical timescales of MMAOs. We argue that the
lack of relatively low mass and young flows in MMAOs is due to the inherent
selection-bias in the sample, i.e. its direct association with 6.7GHz methanol
masers. This implies that methanol masers must switch on after the onset of
outflows (hence accretion), and not before a sufficient abundance of methanol
is liberated from icy dust mantles. Consequently the average dynamical age of
MMAOs is older than for the general population of molecular outflows. We
propose an adjusted evolutionary sequence of outflow and maser occurrence in
the hot core phase, where methanol masers turn on after the onset of the
outflow phase.
