Obstinancy is not a word. It should be obstinance which can be compared to obstinacy. Interestingly, obstinant is not listed in some dictionaries and in others, shown as non-preferred. Obstinateness is also listed as a noun form. As is usually the case with examples like this, there is much overlap; obstinacy and obstinance can often be used interchangeably. There are some subtle differences though. For example, a particular act of obstinance would be called an obstinacy. Example:

"Heather, you are a very stubborn person!"
"Oh really? Exactly what obstinacy have I commited that has so offended you?

If thousands of letters have been written about this, then my take has probably been stated before. Here goes: I'm betting that Trinidad and Tobago, being populated by humans, are not 100% free of religious and racial inequality. I'm also suggesting that the populace and the leaders there have always known this. It would be Naive, at best, to claim in one's national anthem that his or her country is without prejudice. I would suggest, instead, that the anthem is proposing that a land without prejudice is a nationally accepted goal, not a reality. In this case, "find" would be correct as the subjunctive.

While he may not have addressed your question directly, I have to agree with Dyske. Another thing I find awkward is your use of "demand". A demand is a strong call to action. I won't insist it's actually wrong, but to me, demanding an attitude seems a bit awkward.

Weird: "Society demands an attitude of global understanding"

Better: "Society demands that we adopt an attitude of global understanding"

actually, the word "attitude" itself seems superfluous.

Better still: "Society demands that we understand things globally", or something to that effect.

Don't twist it around into a stilted, passive voiced, compromise. As you said yourself, you demand something of someone.

RE: "We learn not to add comparitive [sic] suffixes to words with more than one syllable."

Really? What about happier, sillier, hairier, (nearly any adjective ending in -y becomes -ier, comparatively), simpler, subtler, ampler, brittler, (nearly any adjective ending in -le...) etc., etc....

I have heard "I says" fairly often. Of course, I'm from New York. I don't use it myself. If you think about it, when relating a story, "I said...and he said...and she said...and you said" becomes pretty tedious. I think if you spend some time listening carefully to those around you, you will find that "...said..." is actually not used very frequently in the "correct" way. What you will hear is "...say/says...go/goes/went..." and my personal pet peeve: "...like..." Yes, it's exremely common to hear this. Example: "...And I, like, what are we going to do later? And he, like, I dunno. Let's go to the movies..." Yes, that's right. People use "like" in place of "said" all the time. A few decades ago, it was a teenage thing (think valley-girl stereotype, which, I think, popularized it). Now all those teenagers have grown up.

By the way, there are two issues here. First, the issue of tense. Really, there's nothing inherently wrong with telling a story in the present tense even if you're talking about events in the past. It's done all the time. It's a stylistic way of pulling in the listener, making him or her more involved in the tale. Jokes are almost always told in the present tense: "a guy walks into a bar and asks the bartender...", not "a guy walked into a bar..." So, "...he says...she says..." is usually fine.

Next is the issue of case mismatch. Clearly "I says" should be "I say" but "I says" is a somewhat common idiom (often written as "I sez" in litererature when portraying a colorful character).

As for "go/goes/went", this is also pretty common and was occasionally criticized quite some time ago, but is actually quite logical as well. "Go" doesn't have to mean only locomotion. It can also refer to taking any action, as in "Joe has a funny way of walking. He goes like this..." It's a reasonable extension of that meaning for "go" to refer to speech, i.e., equivalent to "said". In effect, such use is simply a metaphor.

As for "like", well, to me, at least, it makes no sense at all. It has, however, become ubiquitous. Amazingly, I have heard it come out of my wife's mouth and even my own from time to time (rarely)!

This all reminds me of the use of the very common case mismatch, "there's" when it should be "there are" or "there're" (Example: "there's three books you really should read." I would insist that this is bad grammar. I would also accept that I hear this from EVERY SINGLE PERSON I know, at least sometimes, no matter how prescriptively particular they are (including me!)

By the way, my name is not Rene, and I am male, but the original question is about "...her speaking..."

Oh, come on now. Isn't it obvious that when someone says “This is her speaking”, that "speaking" is not a noun? Surely no one actually believes that it's a declaration of "TA DA! I am presenting you with the spoken words uttered by her", and by her, I mean me (don't you hate when someone refers to themselves in the third person? how pretentious!). It doesn't make any sense. While hypothetically, I suppose you could, in some twisted, mangled way, parse the sentence that way, it would be a complete non-sequitor. The only way it would make any sense at all is if the conversation went something like this:

::::: ring, ring :::::
"Hello?"
"Yes, hello Rene. I know it's you. I recognize your voice. You just said 'hello'. Is this 'hello', as well as the words you are about to utter, an example of your, meaning Rene's, actual speech, the audible vibrations created by your vocal cords representing English words?"
"This is her speaking"

Why in the world would anyone delclare that the words they are speaking are examples of their own speech?

Wow, this has ballooned into several issues. First, your question, does "as of yesterday..." mean the same thing as "by the end of yesterday..."? Well, yes and no. I don't think that the words "as of" specifically mean "by the end of"; however, simple logic dictates that if something happens on a particular day, then it must happen by the end of that day. Something that happened yesterday can't have happened after the end of yesterday, can it? Otherwise, it would have happened today, not yesterday, right? So in your case, "by the end of..." really means the same thing.

Next, Dyske's comment about "had finished" compared to, I suppose, just "finished". I don't think it's an issue about durations vs. moments of time. Rather, it's an issue of the type of past tense. "Finished" is the simple past tense; "had finished" is the simple past perfect tense. The simple past perfect tense is used to describe something that happens before something else. The example sentence would make sense using "had" if it looked something like this: "As of yesterday, we had finished three tasks, then Bill quit”, meaning both things happened as of yesterday, but Bill quit some time after we finished the three tasks. I don't know that it's wrong, per se, but using "had" without specifying a second event does leave the reader to wonder, hmmm, what else happened afterwards (but before now) that you're not telling me?

Also note, sometimes "as of" is equivalent to "on", but not in this case. For example, "On Monday, we completed three tasks" means all three tasks were done on Monday. But, "as of Monday, we completed three tasks" only means that they were done on or before Monday. I suppose one could make a case that at least one task would have to be done on Monday, but not all three (I purposely didn't use "yesterday" because "on yesterday" is not commonly said, but I think I illustrated the same point).

You mentioned "on/at", but "as of" can also mean "starting on" or "ending on" and is sometimes the equivalent of "by".

Oops, wrong tense. That's ...maintain...remain..., no "-ed" at the end.

Regarding: "The union, though weak and poor, managed to remain their independence from other big, influential interest groups."

This isn't quite right. I would suggest that it should be either "...maintained their independence from..." or "...remained independent from..."