Merging (renaming) Embedded Data Fields in Target Audience

Hi there, Does anyone have any experience with merging (via renaming) embedded data fields in target Audience? We have a large recruitment survey where we have a range of embedded data fields, and then an updated version of the survey where we have renamed the embedded data fields to get rid of spaces by replacing these with underscores (e.g. initially 'Children under 16', now 'Children_under_16'.) Now, looking at the online help, it seems that if we simply rename 'Children under 16' to 'Children_under_16' then this will effectively merge the two embedded data fields into one embedded data field... But speaking to Qualtrics support, they had not heard of this, and were very concerned that we might try to do this and may potentially lose data....!! Does anyone have any experience in doing this to help give us a bit more confidence going forward? Any thoughts appreciated.