To assess the extent to which HERA S.P.A. should issue hybrid bonds over the next 18 months, several factors regarding its financial profile, funding needs, and historical issuance patterns must be considered:

1. **Historical Issuance & Capital Structure:** 
HERA S.P.A. has never issued hybrid bonds in the past ("First year of hybrid bond issuance: never"). As per the provided guidelines, a company's historical aversion to hybrid bonds is a highly reliable indicator of its future capital structure strategy. The total absence of hybrid bonds in its current capital stack strongly signals that the company has other preferred methods for addressing its funding and leverage needs.

2. **Leverage and Credit Metrics:**
For 2022, HERA's S&P Net Debt / EBITDA stood at 4.23x and its FFO / Net Debt was 17.33%. While Moody's notes a deteriorating leverage trend—likely driven by significant working capital and capex needs as evidenced by the massive surge in revenue (from €10.55 billion in 2021 to €20.08 billion in 2022 due to the European energy crisis)—utilities generally have higher leverage tolerances. Introducing hybrids to artificially support metrics would not align with their historically conservative non-hybrid approach. 

3. **Cost of Debt:**
Macroeconomic data shows a dramatic shift in interest rates in 2022. The 5-year swap curve jumped from -0.264% in 2021 to 1.726% in 2022, and the subordinated delta for non-financial investment-grade issuers expanded significantly (from 1.298% to 2.295%). At these elevated levels, issuing hybrid bonds would carry a substantial premium over senior unsecured debt, materially increasing HERA's overall cost of debt. 

4. **Refinancing and Liquidity:**
HERA effectively boosted its liquidity organically and via standard borrowings, finishing 2022 with a robust cash and cash equivalents position of over €1.94 billion (up from €885 million in 2021). The company has managed to absorb the working capital absorption shocks standard to the utility sector during the 2022 energy crisis without needing to resort to hybrid capital.

Conclusion: Given the lack of any historical precedent for issuing hybrid bonds, the materially higher costs associated with subordinated debt in the current higher-yield environment, and a capital structure that has proven resilient without hybrid support, HERA S.P.A. should not be advised to start issuing hybrid bonds at this time.

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