In order to get 600 additional points I think you should get your PNP nomination under the new "express entry stream" which is yet to be created by the provincial governments. If you have PNP nomination from other existing streams then it may not be eligible to fetch those "600 additional points" for express entry.
Reference: wwwDOTgazetteDOTgcDOTca/rp-pr/p1/2014/2014-12-01-x10/html/extra10-eng.php
FYI look at the last point of Section 5.(1) of Gazzette which says:
5. (1) In order to be "eligible to be issued an invitation", a foreign national must
(a) meet the requirements to be a member of at least one of the classes referred to in paragraphs 2(a) to (c);
(b) meet the requirements of
(i) subparagraph 82(2)(c)(ii) of the Regulations, if they are a foreign national referred to in paragraph 82(2)(b); or
(ii) clause 87.2(3)(d)(iv)(B) of the Regulations, if they are a foreign national referred to in subparagraph 87.2(3)(d)(iii); and
(c) not later than 30 days after the day on which they submit their expression of interest, register with the Job Bank of the Department of Employment and Social Development, if they do not have a qualifying offer of arranged employment or are not named in a nomination certificate issued by the government of a province referred to in paragraph 2(d) under its provincial nominee program "express entry stream" at the end of that period.
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