FWIW, in doing some preliminary testing of OC 8 for Fedora, I noticed that some of the post-2.5.0 commits on the 2.5 branch upstream look pretty significant, e.g.:

https://github.com/doctrine/dbal/commit/8dadeb7ebcfdb1e37e126078260eebee2e401d75
https://github.com/doctrine/dbal/commit/21a2bf6da0e82ae2bd929ae0f45b85eae8aa01b7
https://github.com/doctrine/dbal/commit/aac65338d96ce17cd423c60d4704278877848d16 (and the three subsequent commits)

For my tests instead of building a package of dbal 2.5.0 I built one for the current tip of the 2.5 branch, so far that seems to be working well.