For what it's worth, the KB (95349) for 2019 says this. ( i don't see much in the 2020 KB)
Note: If updating from 2015.2 - 2017.1 the 2018.1 update will need to be installed and all database converted prior to updating to version 2019.1. Please See KB ID:88495 How to update to Sage Fixed Assets Network Edition 2018.1 for details
Note: If updating from 2015.1 and prior the databases cannot be converted directly to 2019.1. They will appears with a Conversion Status of Incompatible Version and will require a PSG engagement to update. Please See KB ID:62949 How do I contact Professional Services Group? for details.
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Rhonda McNamara
Customer Success Manager
Stewart Technologies, Inc.
rsm@stewarttechnologies.com------------------------------