I think this study is really important because too many non-profits ask less or shy away from any ask after a donor has taken a step, which shows a clear sign of deep commitment to the organization.
Although this study addresses planned giving I think the same is true for monthly giving or major gifts. Once donors take these steps to show you they love your charity that is not the time to stop communicating or stop asking.
What the study found was, "The average annual gift among those studied increased by 75% ($3,171) after making a planned gift."
Major gifts, planned giving, monthly gifts are all signs donors are sending that they love what you do. Don’t send them mixed signals after that. Keep doing what got you to that stage.
For example, if direct mail brought you the donor, upgraded their gift and got the major gift, monthly gift or planned gift.... keep sending direct mail.