'Copular', yes; but the following sentences are examples of non-copular uses:
- The meeting will be (held) on the fifth of February.
- He is (located) here.
You appear to be under the impression that the ability to arbitrarily insert supposedly 'missing' participles into the sentence without substantively changing the meaning constitutes some kind of proof that 'be' here is an auxiliary rather than a full copula, whereas all that you have done is change the structure to fit your argument.
Let us look at your 'improved' versions one by one.
Firstly, you imply that
[1] The meeting will be on February 5th.
is actually elliptical for
[2] The meeting will be held on February 5th.
Setting aside, for the moment, the fact that we normally resort to ellipsis as an analytical method only where the original sentence fails to be explicable in terms of normal syntactic relations (patently not the case here), let us indulge your theory for the sake of argument and attempt to determine whether there is true semantic equivalence between [1] and [2].
First off, if we are to accept the premise that participle 'held' is always insertable in statements of this type, then we should presumably be able to change well-formed
[3] The party is tomorrow.
into
[4] ?The party is
held tomorrow.
Oh dear, doesn't seem to work terribly well, does it? Apparently, we would need a participial to-infinitive in this case, viz.
[5] The party is
to be held tomorrow.
OK, so if what is actually missing is a to-infinitive, it should be possible - nay, obligatory, by your lights! - for us to transform [1] into
[6] ??The meeting will be
to be held on February 5th.
Just gets worse and worse, doesn't it?! And the reason? Your original theory is nonsense, since in reality nothing whatever has been omitted from the original, in which the verb 'be', as previously stated, functions as a full copular verb with adverbial complement, a standard, not remotely deviant, analysis according to syntactic norms, from which we need never have departed in the first place.
Next, we have
[7] He is here.
, supposedly some kind of lazy "abbreviation" of
[8] He is located here.
Another fact about ellipses that you seem to have overlooked is that they are generally supposed to be, if anything, more - not considerably less - natural than their abridgments. When we hear one we should - if it is valid - automatically have the comfortable feeling that this really is the restored, full form of the sentence.
I can only presume, then, that you are in the habit of having telephone conversations such as the following:
A: John, where are you located at the moment?
B: I'm located at Mary's. Where are you located?
A: I'm located at the supermarket.
B: But I thought you were supposed to be located at work today!
A: Nah, I was located at work this morning, but then I found that the files I needed weren't located on my desk where I thought they were located, and then, on my way back home to collect them, I saw that there were some great bargains located at the supermarket....
Hmm, very natural!
So, on balance, I think it's safe to assert that your missing participles here are a
figment of your imagination!
PHILO
(Located in Japan)