1. Reg. EC 1151/2017
Annex I subpar. 4.1.
Annex I subpar 4.2
The frequency for product verification performed by the manufacturer saa>hall be based on a risk assessment methodology consistent with the international standard ISO 31000:2018 — Risk Management — Principles and guidelines and at least for Type 1 with a minimum frequency per COP family of one verification per vehicles produced or once per year, whichever comes first.
A sample of three vehicles shall be selected at random in the COP family. After selection by the approval authority, the manufacturer shall not undertake any adjustment to the vehicles selected.

2. COP: current issues
Jan
Feb
Mch
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dez
Situation if one has to finish within 5000 vehicles???
IP1 ~20 000
IP2 ~6 000
IP3 ~10
IP4 ~
SOP
How to finish??? ? ? ?
Overlapping samples belonging to different statistics?
SOP
Production slot for vehicle
Production slot for vehicle
First 3 vehicles are selected in advance
Production slot for vehicle

3. UNECE WLTP COP task-Force Revision on testing Frequency
Mandate of the CoP Taskforce
The CoP Taskforce shall: ..
introduce a harmonised procedure (e.g. statistical approach, sampling frequency etc.) to demonstrate Conformity of Production (CoP) for the Type 1 test in GTR 15 the Type 4 test in GTR 19, and the future UN Regulation WLTP; …
Current EU: 1 sample per 5000 vehicles in an IP-family; at least once per year risk assesment necessary to analyze a sufficient number but  high burden for small and large families << and >> 5000 vehicles / year 3

4. Limit number of samples per year for large families
UNECE WLTP COP task-Force Revision on testing Frequency
Proposal:
Allow for COP-families under certain conditions for small families, e.g.
Split IP-families due to exceedance of max. range (30g/km)
Same engine, same drivetrain, same emission character but different engine power
Same engine, same gearbox but 2WD/4WD
Separate IP-families only due to gear ratios difference
Extend to 2 year-period to finish the sample for <1000 veh/y …
Limit number of samples per year for large families 4