What applies to your products in terms of deadline when your products and Quality systems must meet MDR completely?
CAMD publiced a document with the most common qestions and answers which can be found here!

Note that for products that can be sold after May 25, 2020 No significant changes in the design and intended purpose can be made. And no new products can be released.

Certain areas of MDR must be meet for all products May 25,2020. There are exceptions for each of them why you should read the carefully if you plan to implement this later.

a. Registration of economic operators and of devices

b. Post market surveillance (PMS)
c. Market surveillance
d. Vigilance
e. A valid EC certificate
f. Be compliant with MDD