OEIC investment (accumulation shares) for grandchildren (cashing out after 18 yrs)

Pricklyhedgehogs

Many thanks @Malthusian and @[Deleted User] , for your latest comments. This has helped me a lot in understanding the way forward with all of this.
By my calculations, (thanks again to Malthusian's earlier post) the kids, with their own CGT allowances for this tax year and next (£6k and £3k) will not have any tax liability.  They are wanting to take some money/cash in shares asap (70%) and are happy to leave the rest until after April. 
There (fortunately for them) has never been any question that the money is theirs and Dad wants this sorting asap for them, and will be immediately bank transferring them their money once received from HSBC.