During checkpoint reconciliation, if an out of order timestamped update is encountered in the update-chain, then special logic of out of order timestamped processing is triggered. As part of this processing timestamps of the updates in the update-chain are modified. 

Modifying updates in the update-chain during checkpoint reconciliation should not be done, as the update-chain is accessed in shared mode. 

This issue is present only for the out of order timestamped processing, but not for the mixed mode timestamped processing.  The processing of the update chain by both the out of order timestamped processing and by the mixed-mode timestamped processing should be the same.