CKeditor does not seem to be rendering the correct text colour when retrieving data? - ckeditor

Question

I asked about this question a few months back, but unfortunately it has not solved my issue, so I am asking it again with more information.
I am using CKeditor 4.4.5
Original Question
I have experimented with the online demo of CKeditor. What works is that the colour is rendered when making the edit in CKeditor, however when one retrieves a content with the coloured span element within it, as it correctly should do, the colour is not rendered in CKeditor. Also it seems that tags are not being stripped out at all. It just seems that CKeditor is not rendering something like :
<textarea class="RTE" cols="20" disabled="True" id="Content" name="Content"
rows="2">
<h1><span style="color:red">I should be coloured red</span></h1>
</textarea>
with:
I should be coloured red
in red.
I have checked for "!important", in relevant CSS, and I cannot see any that would affect this text.
Thoughts on why CKeditor is not respecting the "color" attribute of this "span" element when retrieving/displaying data, rather than initially editing it would be very helpful.
Thanks in advance.
EDIT
Source in "source" view:
<h1><span style="color:red">I should be coloured red</span></h1>
EDIT2
This works:
<p style="color:red">I should be coloured red</p>
EDIT3
This works
<h1 style="color:red">XXX red text XXX</h1>
EDIT4
This does not work:
<p><span style="color:red">XXX red text XXX<</span></p>

Answer 1

It seems I have some code in my CKeditor config which is causing this behaviour, but not sure why. When I comment it out, my colour coding works. Also I have turned ACF off, as I fine all my inline style attributes gets stripped out. So I have altered my config to :
//config.protectedSource.push(/<span[\s\S]*?\>/g); //allows beginning <span> tag - now commented out
//config.protectedSource.push(/<\/span[\s\S]*?\>/g); //allows ending </span> tag - now commented out
config.allowedContent = true; //Added