To assess the suitability of REDEIA CORPORACION SA for issuing hybrid bonds, we evaluate the company's financial profile, sector characteristics, and the provided specific data points against the given guidelines.

**1. Sector Characteristics and Cash Flow Visibility:**
Redeia Corporacion (formerly Red Eléctrica) operates primarily as the transmission system operator (TSO) for the Spanish electricity grid. As a regulated utility, its revenues are dictated by a well-established and transparent regulatory framework. This provides the company with highly visible, stable, and predictable cash flows. Such "infrastructure-like" characteristics make it a prime candidate for hybrid bond issuance, as rating agencies and investors are comfortable with the stability of its underlying business model. 

**2. Investment Grade Profile and Financial Metrics:**
The company’s S&P FFO / Net Debt ratio of ~20.6% and a Net Debt / EBITDA ratio of 3.21x are highly commensurate with a solid Investment Grade profile (typically in the BBB to A- area). While Moody's adjusted leverage trend is "improving," the company is undergoing significant capital expenditures. In 2022, cash flows used in investing activities saw a massive increase to €1.64 billion (up from €537 million in 2021), reflecting necessary investments in the energy transition and grid infrastructure. Hybrid bonds allow utilities like Redeia to fund such heavy capex pipelines without worsening their senior leverage metrics, thereby defending their current rating and maintaining rating headroom.

**3. Historical Issuance:**
A critical factor in this assessment is the explicit data point stating that the entity has issued hybrid bonds ("Issued hybrid bonds in 2021 or 2022: yes", with the first issuance marked for 2023). According to the guidelines, an entity that actively participates in the hybrid market is a strong signal that it has established institutional access, a credible financial policy for managing hybrid instruments, and an ongoing rationale for their use (in this case, funding green capex and defending senior ratings). 

**Conclusion:**
Given its status as a regulated utility with highly predictable cash flows, its solid investment-grade profile, its significant capital expenditure funding requirements, and its proven track record as a hybrid bond issuer, Redeia Corporacion perfectly fits the "Strongly Suitable" category for hybrid debt issuance.

<answer>Strongly Suitable</answer>