Nil rate band for discretionary trust

Hi everyone
Please can someone advise whether the nil rate band for a discretionary trust will renew after a certain period, or if it only gets one for the entire duration of the trust? I have been looking for the answer without success, and I can’t remember from when I did my STEP exams.
If someone could confirm for me, I would be very grateful. I have a client approaching the ten year anniversary charge and need to confirm their liability.
Thank you so much.

At each ten year anniversary a charge may arise on the trust property. To calculate the amount of the charge it is assumed that the IHT table is joined taking into account “the chargeable transfers made by the settlor within the seven years (A) before the settlement was made plus any chargeable transfers made by the settlement in the previous ten years” (B).

[A + B] is then reduced by any available NRB at that time. Effectively, at each ten year anniversary it is assumed that there is available a NRB of an amount relevant at that time.

The chargeable transfers made by the settlor within the referred to seven years never fall out of account.

Malcolm Finney

Hi Malcolm
Thank you so much for taking the time to reply, I really appreciate it.
Best wishes
Hannah