Key legal question
Whether the public-law appeal remained admissible despite the applicant's letter that could be read as a withdrawal.
Extracted holding
No valid waiver or withdrawal could be inferred, because the letter was sent before the applicant knew the reasons for the challenged decision.
Extracted reasoning
A renunciation of the remedy is effective only if made after the party has learned the decision and its grounds. Here the letter and notification crossed, so the applicant retained a legal interest in challenging the refusal.