Anniversary (ie 10 year) charges would apply. The ten year anniversaries are based on the date the trust was created ie date property was first comprised in the trust,2005, (not date when bond was added to the trust under the will, 2007).
Was the bond a single bond or a cluster of identical bonds? This will impact on tax liabilities where encashments are made (Shanthiratnam v HMRC 2011].
Offshore bonds give rise to no 20% tax credit. Trust rate of 45% applies to chargeable event gains. Appointment to trust beneficiaries may be tax efficient on any event gains.
Assume trust is UK resident and original settlor UK domiciled.
Malcolm Finney