Delay in start date from date of entry in UK - impact on ILR

[Planning]

Hi

I am preparing to submit my ILR, but am very concerned with the delay in my start of employment in UK from the date of entry to UK. This is because when I got my work permit, I travel to UK for a familiarisation trip and look for houses in may 2012 (which I revived a dated stamp on my visa) for 7 days. I return back to my home country, and only came back to UK to start work on 12 July. The below is the critical date:

Date of entry clearance issued : 10 March 2012
Date of entry into UK : 10 May 2012
Date of start employment in UK: 12 July 2012
Expiry of my work permit/ visa: 30th June 2020

I am now preparing to apply for ILR, as my first arrival start on 10 May 2012. However in my employer start date letter, it will be 12th July 2012. I’m wondering if the Qualifying Period would be from 10th May 2012 or 12th July 2012? And whether the delay in employment start date from the entry to UK date would jeopardize my application