Mainiac1957 usually sponsors an annual spring CITO event, taking part in the annual Brewer/Bangor River Cleanup Day.
Other than that, I know GCM.org members have hosted CITO events, but not sure if they have been in conjunction with CITO Day.
I would like to do it here on earth day like other parts of the country but..... In April there is generally too much snow. I have done mine in May every year and it has worked out. The date is subject to change but it should be the 16th I believe.