Hello all, this is mostly for information only.
There is a proposal to improve the definition of
https://schema.org/isBasedOn (which equivalent to the original
LRMI property IsBasedOnUrl
 The current suggestion is that the definition be changed to
A work from which this work is derived or of which it is a modification or adaption.That wouldn't have any consequences I can see for the LRMI version, but if you have any comments add them to the GitHub discussion 
PJJK Limited: technology to enhance learning; information systems for education.
CETIS LLP: a cooperative consultancy for innovation in education technology.
PJJK Limited is registered in Scotland as a private
limited company, number SC569282.
CETIS is a co-operative limited liability partnership, registered in England number OC399090