EBU Single Rulebook Q&A 22 July 2022 2022_6522 Treatment of additional collateral on top of overcollateralization of Covered bond program

Should a surplus above overcollateralization (above contractual amounts/percentages and also above what rating agencies require to maintain the rating) within a covered bond programme be considered as encumbered, when release and re-assignment of any security requires a signature from external parties (incl. the trustee for the covered bond programme) based on the programme documentation?