The annex I of CRR states that undrawn credit facilities can be considered as low risk items if they can be automatically cancelled due to deterioration in a borrower’s creditworthiness:

4. Low risk:

(a) undrawn credit facilities comprising agreements to lend, purchase securities, provide guarantees or acceptance facilities which may be cancelled unconditionally at any time without notice, or that do effectively provide for automatic cancellation due to deterioration in a borrower's creditworthiness. Retail credit lines may be considered as unconditionally cancellable if the terms permit the institution to cancel them to the full extent allowable under consumer protection and related legislation;

The text uses the term “may be cancelled” which seems to indicate that we must rely on the terms of the contract to define whether a commitment is UCC or not.

The term “provide” also indicates that the bank must have the right to cancel but do not have to demonstrate that the cancelation is systematically cancelled whenever the borrower’s creditworthiness is downgraded.