ANSWER (from own knowledge; Greek Code of Civil Procedure, KPolD, as in force October 2026)

Step 1 - Which time limit applies.
Art. 518 par. 1 KPolD: the appeal (efesi) against a first-instance final judgment is filed within 30 days from the service of the judgment, when the party resides in Greece. The company is seated in Heraklion, so it resides in Greece. The 60-day limit for parties abroad or of unknown residence does not apply. The limit runs from service because the judgment was served at the plaintiff's initiative, on Thursday 16 July 2026.
The alternative limit of art. 518 par. 2 (three years from publication, when the judgment is not served) does not apply, because the judgment was served. Publication on 2 July 2026 is therefore irrelevant to the start of the period.

Step 2 - Start of the count.
Art. 144 par. 1 KPolD refers to the Civil Code rules on time limits (arts. 240-246 AK). Under art. 241 AK, the day of the triggering event (the day of service, 16 July 2026) is not counted. Counting starts on the next day.

Step 3 - Judicial vacation.
Art. 144 par. 3 KPolD: the judicial vacation (1 July to 15 September) is not counted in time limits for ordinary remedies, so the running of the period is suspended during it. Service fell on 16 July, inside the vacation, so no day of the 30 elapsed before the vacation. The period begins to run on 16 September 2026, the first day after the vacation ends on 15 September. Day 1 = 16 September 2026.

Step 4 - Count the 30 days (art. 518 par. 1 KPolD with art. 242 AK, a period in days ends at the end of its last day).
16-30 September = days 1-15. 1-15 October = days 16-30. Day 30 = Thursday 15 October 2026.

Step 5 - Extension for a non-working last day (art. 243 AK, applied through art. 144 par. 1 KPolD).
15 October 2026 is a Thursday and is not a public holiday (28 October is the national holiday, which is later). No extension is needed.

Cross-check without the vacation rule: 16 July + 30 days = 15 August 2026 (Saturday, and the Dormition holiday), which art. 243 AK would move to Monday 17 August 2026. The vacation rule of art. 144 par. 3 is what makes the later date, 15 October 2026, control.

Conclusion: the last day for filing the appeal is Thursday 15 October 2026.

RESULT: deadline = 2026-10-15; rule = Art. 518 par. 1 KPolD (30 days from service), with art. 144 par. 1 and 3 KPolD (counting by the Civil Code; judicial vacation 1 July-15 September not counted) and arts. 241-243 AK
