What happens if EHE and others have to pay normal interest rates...

What happens if EHE and others have to pay normal interest rates that match the risk for the RAD? Also what are the likely limits to debt that would be reasonable? Seems to be like mezzanine finance but at term deposit rates? Also Ebitda is about 90m, net debt is about 857m. That is about 10x EBITDA, where a normal covenant would be maybe 3.5 times - but admittedly that doesn't take into account developments funding that would be covered by different development finance. What if EHE needed to comply with normal lending covenants rather than risking residents fiances without normal market reward for risk?
It looks like they would be a risk of insolvency???

Keen to get some understanding of why there appears to be confidence that this arrangement will be ongoing without some big changes.