Albert suggested that perhaps it would be better to finish off this season of procurement tennis with a general analysis of Part 5 (paragraphs 115 - 122) instead of going article by article and I agree with his view. Therefore this is "the end", the final entry for the #pubcontregs2015...
Part 5 starts with yet another typo, again providing a clear indication of how rushed the regulations were back in February. Regulation 115 epigraph reads "Interpretation of Part 6" which is non-existent, whereas its Paragraph 1 mentions that "[i]n this part [...]." This is simply a typo, but one which could have been avoided.
Most of the Regulations in Part 5 deal with the transition between previous Regulations and the current Public Contracts Regulations 2015 and do not warrant significant comment. Regulation 117 clarifies that nothing in this Regulations affects public works concessions as defined in the 2006 Regulations (although Regulation 116 revokes the 2006 Regulations tout court...)
Regulation 120 provides a temporary exemption for certain NHS procurements until April 18th 2016. This exemption covers procurement of healthcare services for the NHS within the meaning and scope of the National Health Service (Procurement, Patient Choice and Competition) (No. 2) Regulations 2013. From April 2016 onwards, the Public Contracts Regulations 2015 apply instead except whereas there are specific exclusions.
Regulation 121 offers contracting authorities some flexibility on how to organise their procurement procedures until October 2018 when all procedures are to be done electronically. It is not clear to me if it applies only before each of the situations described in Regulation 1(a) to (c) occurs (ie, in the "transitional period") or if it applies after electronic procurement is supposed to be mandatory under each of those sub-paragraphs. I suspect only the first is compatible with Article 90(2) of Directive 2014/24/EU.