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The current state-of-the-art lens monitoring campaign, COSMOGRAIL, typically visits each of its target every few nights during each of several observing seasons each lasting many months. For example, \citet{TewesEtal2013b} present 9 seasons of monitoring for the lensed quasar RXJ1131$-$1231 where the mean season length was 7.7 months ($\pm 2$ weeks) and the median cadence was 3 days. These observations were taken in the same R-band filter, with considerable attention paid to photometric calibration and PSF estimation based on the surrounding star field. This data allowed \citet{TewesEtal2013b} to measure a time delay of 91 days to 1.5\% precision.   While this quality of measurement is possible for small samples (a few tens) of lenses, the larger sample of lensed quasars lying in the LSST survey footprint will all be monitored over the course of its ten year campaign, but at lower cadence and with shorter seasons. We can expect the mean cadence to be around 4 days, but this is in any filter; the gaps between observations in the same filter will tend to be longer \citep{IvezicEtal2010,LSSTSciBook}; the season length is likely to be approximately 4 months (with variation among filters), in order to keep the telescope pointing at low airmass.