If I decide to do a lump sum contribution of $75000 to the 529 plan on July 1, 2018, is the contribution considered as a one-time contribution or contributions over 5 years? If it is considered as contribution spread over 5 years, does it mean that it is not considered as $15000 contribution on July 1 2018, $15000 on July 1, 2019, $15000 on July 1, 2020, $15000 on July 1, 2021, and $15000 on July 1, 2022? If end up in nursing home in January 2022 and run out my asset in December 2023 and need to apply for medicaid, will any part of my lump sum contribution to the 529 plan as described above subject to medicaid look back?