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{The variability study of 6.7\,GHz methanol masers has become a useful way to improve our understanding of the physical conditions in high-mass star-forming regions.} {Based on the single-dish monitoring using the Irbene telescopes, we selected three sources with close sky positions.} {We imaged them using the European Very Long Baseline Interferometer Network and searched available data on VLBI archives to follow detailed changes in their structures and single maser spot variability.} {All three targets show a few groups of maser cloudlets of a typical size of 3.5\,mas and the majority of them show linear or arched structures with velocity gradients of order 0.22\kms\,mas$^{-1}$. The cloudlets and overall source morphologies are remarkably stable on time scales of 7-15\,yr supporting a scenario of variability due to changes in the maser pumping rate.}, Comment: 20 pages

The Maser Monitoring Organisation (M2O) is a research community of telescope operators, astronomy researchers and maser theoreticians pursuing a joint goal of reaching a deeper understanding of maser emission and exploring its variety of uses as tracers of astrophysical events. These proceedings detail the origin, motivations and current status of the M2O, as was introduced at the 2021 EVN symposium.