Hello,
Reading th SUM, It appears that you have to set the processing baseline on the command line, and that 99.99 is the default.
And the ESL_L2A confirm that it is not a bug, but a way to identify products generated in stand-alone mode and not by the PDGS. They note that with the previous version (2.5.5) it was only replicating the L1C baseline number.
Cheers
Jan