MyPlanner rebranded from SMSF Partners in 2014 and recruited Philippa Sheehan from the IOOF network shortly thereafter.
In a letter from Mr Mardell to authorised representatives — seen by SMSF Adviser sister title ifa — the dealer group announces that Ms Sheehan has resigned from the post effective 23 April.
"After a long and successful career, Philippa has made the decision to retire and she is proud of her time at MyPlanner," Mr Mardell wrote.
"The shareholders and board would like to thank Philippa for her contribution to the business and her continued passion for the industry."
She has been a longstanding advocate of "non-aligned financial advice" and of raising the number of women at executive level in the wealth management industry.
ifa understands Ms Sheehan will take a break from the financial services industry to spend time with her young family.
ASIC placed licence conditions on MyPlanner in December 2017.