Yeah this has come up in our local group a few times. I've been logging activity at a house in the valleys for about 18 months now and I honestly can't find a solid pattern tied to the lunar cycle, but two of the other investigators swear by it.
What I have noticed is that the family living there reports more disturbances when they're stressed or sleep deprived, and obviously a full moon can mess with sleep so maybe thats the link rather than anything directly lunar.
There's an older theory in poltergeist research that the activity feeds off the emotional state of a focal person rather than external conditions. Worth considering before we chalk it up to the moon itself.
That said I'm not dismissing it, I'd love to see some actual logged data from people here. Dates, times, type of activity. Even rough notes would be interesting to compare. Anyone keeping records?