Did Cuthbert & Wilfred Collingwood both fail to pass their Lieutenant's passing examinations on 06 October 1770?

If not, then what is the explanation for why Cuthbert's "In pursuance" date is 06 October 1770 and and his certificate is dated 07 April 1772 and Wilfred's "In pursuance" date is 02 March 1772 and his certifcate is also dated 07 Apr 1772; HOWEVER, the list of sea service claimed for both is as of October 1770. All the listed sea service claimed was preformed under the command of their cousin Captain Richard Brathwait whose brother-in-law, Gustavus Logie, also served on the Shannon, Gibraltar and Liverpool. Logie's "in pursuance" date was 08 Oct 1770 and his certificate was dated 09 Oct 1770. The sea service time aboard Liverpool for all three young gentlemen was listed as 2 years, 12 months, 0 weeks and 2 days (where "months" were "pay months" of four weeks duration each).