Its good you pole can move a little.
When they design sky scrapers, they can move as much as a metre in the winds. With last nights winds my 2"" poles are moving a round a little but to me that,s a little give putting less stress on it but can pull on your antenna a bit especially if its a tuned length unlike me G5 is no worries unless it snaps. But mines not set tight for that reason it does get pretty wind up here on a hill and did last night
You could Guy rope off your pole is another idea.
But yes chat to your local scaffy people and ask them to deliverer when inpassing. Must have chat with mine as I need some spinning clamps.
Yes, I agree with Karl, a bit of swaying is quite healthy - that’s how trees cope with high wind :o)
If you do add guys, either put them above the middle, or below it. If you guy it in the middle, it will resonate in high wind, and likely snap - think suspension bridge disasters!
(Middle, in this context, should include the effect of whatever aerials are fixed to the top. Having fitted the guys, give the pole a slow shake, and check that it quickly stops when you let go. If it keeps whipping back and forth, change the guying point).
I have a 20 foot 2 inch thin walled aluminium pole supporting a white stick co-linear, and the mid point of a doublet. It is fixed at the base, and at a point about six feet up. It started out some years ago as a temporary arrangement, but has held up well so far.
Will remember than when I guy off me support pole with the beam on it.
So on my 20ft pole wants to be about 12ft to 14ft. No Lower. Or the total height including the beam above half way as the Hex adds about another 4ft Now thinking about it, so 16 to 18ft would be better yes.