# Junior Fees Implementation Summary

Based on the recent updates, we have introduced a dedicated system for tracking, displaying, and reconciling junior team attendances and payments. 

## 1. Implemented Features
- **Dual-Sheet Architecture:** The system now pulls attendance from two separate Google Sheet tabs—one for adult practices and another for junior practices.
- **New Views:** 
  - `/fees-juniors`: A dedicated dashboard showing junior attendances and calculated fees.
  - `/reconcile-juniors`: A dedicated page matching Fio bank transactions against expected junior fees.
- **Granular Attendance Display:** The UI clearly separates and tallies adult (`A`) and junior (`J`) practice counts for each member (e.g., `4 (2A+2J)` or `2 (J)`).

## 2. Membership Rules
- **Identification:** A member is processed as a junior if they appear in the *Junior Sheet*, UNLESS:
  - They are listed below the separator line `# Treneri` (or `# Trenéři`).
  - Their tier is explicitly marked as `X`.
- **Adult Sheet Fallback:** Members from the Adult Sheet whose tier is marked as `J` are also tracked as juniors.
- **Merging Identities:** If a member has the identical name in both the Adult Sheet and the Junior Sheet, their attendance records are merged together into a single profile.

## 3. Fee Calculation Rules
The base fee calculation for juniors relies on the total combined attendance across both adult and junior practices for a given month:
- **0 attendances:** 0 CZK
- **Exactly 1 attendance:** `?` (Flags the month for manual review/decision)
- **2 or more attendances:** 500 CZK (Default base rate)

## 4. Exceptions & Overrides
We have hardcoded specific timeline and pricing exceptions directly into the logic:

- **Modified Monthly Rates:** 
  - **September 2025** (`2025-09`) is explicitly configured to have a fee of **250 CZK** for 2+ attendances instead of the default 500 CZK.

- **Merged Billing Months:** 
  To handle holidays and off-seasons, certain subsequent months are merged and billed as a single period. Their attendances are summed up before the fee rule is applied. The current active merges are:
  - **December 2025** is merged into **January 2026**
  - **September 2025** is merged into **October 2025**