One major feature of the Ignition platform is the “Store and Forward” system that provides a local cache prior to SQL database writes. This can lead to performance gains for high speed logging and naturally lends itself to caching in the event of loss of database connectivity. Is probably your cleanest way ahead. I would contact the sales team for a quote to see what kind of upgrade options you have.
Colby or Travis should be able to help you with possible options with the legacy FactorySQL package. I emailed them a heads up.