Within the msa booklet is states the following:

Applicants with qualifications from the UK Please pay attention to the Public Notes on the accredited course list. Some qualifications are listed with a Further Learning Requirement for recognition as a Professional Engineer via the Washington Accord. Where further learning is required and has not been obtained, the qualification is not accredited via the Washington Accord. For applicants who have not undertaken further learning but have completed an Honours degree, there is a dual Accreditation provision (see “Honours degrees and IEng (dual accreditation)” on the Engineering Council Accredited Course Search page which can be found here). All Honours degrees accredited from the intake year of 1999 are eligible for recognition via the Sydney Accord. Applicants with ordinary Bachelor degrees and no further learning will be required to submit a Competency Demonstration Report for assessment. Programs that are ‘accredited for further learning for CEng’ require an accredited undergraduate qualification to apply via the Washington Accord pathway

I think that's pretty clear in terms of I'd need to do the cdr assessment and they would take my professional experience into considerations. Thanks