As you know, Standard Edition RAC is discontinued after Oracle 18c. My company has elected instead to take advantage of a (in my opinion) "High-ish" availability feature in Standard Edition under 19.7, which essentially is an active/passive architecture. From everything I have seen, this looks like it should work similar to a one node RAC in so far as your existing failover notices should still work, and I suspect (though I haven't seen a whole lot of application developers' oriented documentation on it) that al the existing connection URLs you would use for connecting to RAC will still apply in this 19.7 High Availability architecture. The main difference is of course no load balancing as only one node is ever active at a time.
I wanted to reach out to others who have already adopted this architecture which my company will soon be standing up to see how their real world experience stacks up and what we should be aware of issue wise.
Thanks,
Joe