EIOPA explanation of treatement with covered bonds under concentration risk is as follows:
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1)
Each covered bond issued by the same counterparty should be treated as a separate single name exposure. In the example provided one would therefore have (bond A and covered bonds B and C are issued by the same counterparty):
SINGLE NAME EXPOSURE 1.1 - bond A
SINGLE NAME EXPOSURE 1.2 - covered bond B
SINGLE NAME EXPOSURE 1.3 - covered bond C

2)
Based on the answer in 1) the calculations of the relative excess exposure is straightforward (for bond A based on Article 185 and for the covered bonds B and C based on Article 187(1) Delegated Regulation (EU) 2015/35).
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I want to clarify my understanding (1) and have one more question (2):
(1) I understand the point 1) as follows: Each covered bond in the portfolio is treated as a separate single name exposure. Therefore if company buy 10 covered bonds, irrespective of their CQS and issuer, there will be 10 single names in the concentration risk. Is that so?

(2) In the point 2) EIOPA states that the calculation of excess exposure for single names with covered bond (1 single name = 1 covered bond) is done based on the Article 187(1) of Delegated Regulation 2015/35. Nevertheless, I do not understand how I should assign excess exposure to single names that are formed by covered bond with CQS =2 or higher (or unrated). The mentioned article defines the excess exposure for covered bonds with CQS = 0 or 1. For the covered bonds with CQS = 2 or higher I think that correct way would be to apply Article 186. Therefore in my example above (in the question 1454) following would apply:
SINGLE NAME EXPOSURE 1.2 - covered bond B (CQS=0) -> CT=15% according to Article 187(1)
SINGLE NAME EXPOSURE 1.3 - covered bond C (CQS = unrated) -> CT = 73% according to Article 186(1) because weighted average CQS = 5 (Article 182(5)).
Could you confirm my understanding?