...as the times in your logbook will tie up with the airfield logs that the CAA will look at...
Well, considering that the CAA does not have or hold copies of your logbook, and also does not have or hold copies of the airfield logs, and considering that the CAA does not have unlimited resources, I'd say it is very, very unlikely that the CAA will compare your logbook with the airfields logbooks in routine cases.
If they suspect a massive case of fraud they might, but not for the routine issuance of a CPL/ATPL.