Can you provide a link to exactly which part of the UK AIP you are referring to? I've just looked at both Edinburgh and Glasgow SIDs and both state in the General Information section at the bottom the very standard phrase "Maximum 250KIAS below FL100 unless otherwise authorised." I have yet to see a UK SID chart that doesn't have that written on it.
You can see the Edinburgh SID charts on the AIS website
here and the Glasgow ones are
here