NEC3 ECSC: Can I modify to an ECC?

Was any consideration given to the ECSC having a reimbursable option? Much of the work my company do is under a framework and needs to be responsive to emergency works. Having agreed levels of fee and rates (that are used as Defined Cost), would it be easy to modify the contract to work like Option E of its big brother?

Not without quite a few amendments - which will bring it in line with option E but then again by far the easiest way to do that would be to use option E! Rightly or wrongly making a short contract a reimbursable one will not be the straight forward contract the short contracts intended.

Not impossible though I am sure (especially where there is a will by both Parties for this to happen)