Great post. An interesting thing about the background state this year. Its actually really favorable for mjo wave propagation, it would seem. Solar correlation is suggested in research to have a lag ~3 years. East QBO. La Niña.
https://journals.ametsoc.org/view/journals/clim/33/1/jcli-d-18-0811.1.xml?tab_body=fulltext-display
Specifically, under cool ENSO, easterly QBO, and SMIN conditions, evidence favors a strengthened wave train that propagates farther eastward and more strongly modulates SLP and SAT anomalies. The modulation is increased further when two or more of these conditions are simultaneously in effect. While internal intraseasonal variability is large and these influences may not be apparent during a given MJO cycle in a given winter, the length of currently available reanalysis datasets allows them to be detected via averaging and construction of mean MJO phase composites.