Test feasibility of Oracle 19c as pluggable replacement for Oracle 12.2c

hramihaj amackenz@redhat.com cbartlet we have a support exception request with the following info:

Base on the analysis presented in [1]. It's our understanding that it's technically feasible to support Oracle 19c because it should be treated as Oracle 12 which is actually supported.

"Beginning with Release 12.2: New releases will be annual and the version will be the last two digits of the release year. The release originally planned as 12.2.0.2 was released as 18, and the release originally planned as 12.2.0.3 will be release 19. For Lifetime Support purposes, Releases 18 and 19 will be under the 12.2 umbrella. Release 19 will be the last release ("long term support" release) for 12.2"

[1] https://access.redhat.com/solutions/3624641

Based on this info 19c should potentially be backwards compatible with 12.2c. How much effort and time would it be do a smoke test whether it is a pluggable replacement? If the smoke test passes could we give a support exception?