Hi @Tommy Dang ,
TBC projects are not individual files (like Terramodel or DWG) , but rather file + folder (like 12d).
Your work around is actually the best solution there is. Simply "Save As".
Another option would be to "Archive" the Project, then the "ZIP" file is created, but I do not think that it would address your issue.
I can see the need to rename the file (e.g. you're saving on Trimble Connect and want to see full file history in "Activity") for traceability purposes.
Are you trying to rename major project with heaps of data in it, or rather a file with daily survey data?
If the latter is true, it would be bit easier if you were after saving (and renaming) VCL file, not the VCE Project, then simple rename would do.
Sitech Construction Systems has very good customer support, I'd imagine that similar is true for Sitech Solutions.