It's probably too late for you to notice my reply, but I would look at your total skill set and get into consulting those very specific skills. Not the generic ones everybody has, but the solutions you have gotten really good at over time. Make those things your Value Proposition. Everybody does similar things in your biz. But you do
this specific thing that your potential customer needs. No exec is interested in tech. They're interested in your Value Prop. Period.
I've spent my life consulting and am semi-retired now (I'm still more than a decade from retirement age), but I got here by re-inventing myself over and over again as needed for particular targeted gigs. The skills stay the same, and even my title doesn't change much, but the Value Proposition is the only you are selling, and the only thing an exec is interested in. That part changes as required, and always really specific to the potential customer's needs.
I cozied up to other consulting firms and did my magic as both strengthening their services, shadowing under their company name, and adding new services that they didn't have until then, in which case I'm more at the forefront, and not shadowing. Check the ego at the door, 'cos shadowing services makes a lot of money. I used to be on the bleeding edge, but found it far more lucrative to help my customers be there instead.
I stay away from groups that cater to my business area, because they are primarily focused on permanence, and are merely echo chambers for people who do what you do in permanent positions, instead of true consulting. Instead I focus on the peripheral areas - executives mainly.
If they can't sign a cheque, they are not my target audience for interview, or even discussion about a gig. Money is a different game altogether when you aren't an employee for a big box biz. Most workers don't realize they get farmed out for 4 or so times more dollars than they get paid. As a consultant, that money is yours. It pays for the time between gigs when you are working toward your next customer, advancing your skills, etc. It's a lot more money, but you also need to use it to keep your consultancy alive. So I haven't talked to an HR person since I was a teen. HR and most head hunters are about permanence. The big money is where they are not part of the picture.
This will sound counter-intuitive, but I rarely ever talk to tech people, even though my work is nearly entirely technical. I speak directly to execs and people who have authority to hire me directly. Anyone else is just too much work, because anyone who can't sign a cheque is just another gatekeeper.
At 40 it's pretty much an ideal time to use your maturity as a sellable feature. It's pretty much all I've ever done since the 90's.