  Orbital monitoring of M-type binaries is essential for constraining their
fundamental properties. This is particularly useful in young systems, where the
extended pre-main sequence evolution can allow for precise isochronal dating.
Here, we present the continued astrometric monitoring of the more than 200
binaries of the AstraLux Large Multiplicity Survey, building both on our
previous work, archival data, and new astrometric data spanning the range of
2010-2012. The sample is very young overall -- all included stars have known
X-ray emission, and a significant fraction (18%) of them have recently also
been identified as members of young moving groups in the Solar neighborhood. We
identify ~30 targets that both have indications of being young and for which an
orbit either has been closed or appears possible to close in a reasonable
timeframe (a few years to a few decades). One of these cases, GJ 4326, is
however identified as probably being substantially older than has been implied
from its apparent moving group membership, based on astrometric and isochronal
arguments. With further astrometric monitoring, these targets will provide a
set of empirical isochrones, against which theoretical isochrones can be
calibrated, and which can be used to evaluate the precise ages of nearby young
moving groups.
