We haven't seen any reports of issues with pension splitting. If entries are changed or additional information added after the split has been performed, the numbers on the Joint Election to split would also need to be updated.
In other words, if any info in your return changes after running the pension splitting optimizer, the optimizer should be run again to take the info into account.
If you would like to speak to a phone support agent about your split numbers,
https://turbotax.community.intuit.ca/replies/3152013