No response from co-trustee for 6 months

Hi all

We act as professional trustees in a trust with a lay trustee in a Will trust. Back in December, he mooted retiring and appointing someone in his place, but since has not responded to any correspondence I have sent him.

The Will contains no STEP provisions, only administrative provisions that do not contain any provisions related to appointing or removing trustees.

I think my only option therefore is to rely on the Trustee Act 1925 - I cannot rely on Saunders v Vautier to close the trust because the beneficiaries are minors.

I think I can rely on s36 - “(1)Where a trustee, …or refuses …to act” (as I would wager that not responding amounts to a refusal to act, particularly when he has not turned up to the past couple of annual meetings for one reason or another), but I am unsure for how long he has to not respond for. I am tempted to take the view of 12 months (due to the other reference in the same section about being outside of the UK). What are people’s thoughts or is there a leading case on what amounts to refusal to act?

Thank you all in advance!