I'm not quite sure I understand the question? Did you do 19 hrs of flight training towards a PPL, or do you already have one.
In any case, one hour of flight time is exactly that, and it will remain so forever.
If you may count that hours towards the requirements for issuance of a certificate or rating would depend on the exact wording of those requirements, but I believe that this, in most cases, should not be a problem at all.
Happy flying
