I am sure that Support would find a way for you to access the account, maybe there is a way of you demonstrating that you owned the now defunct e-mail (a copied email, yahoo telling you you can't reactivate it or something) - maybe you could demonstrate your ownership by detailing info about the account / commander - how long you had it, progress, why you stopped playing and when...
Failing that (or in the interim) - Commander Deluxe edition (Commander Pack) is on sale on Steam for £11.99 at the moment.
BTW current level? if you have not played long enough for yahoo to delete the email then how come?
Sorry; not quite sure what you meant by the last bit. I've about 2000 hours of play, but I've had the GAME for several years. How long, I'm uncertain; please understand that the grey matter inside this particular brain housing group has taken a helluva beating - both physically and metaphorically (getting hit by an RPG is not something I recommend for long-term health benefits) - and memory is nowadays less an accurate recording than a kaleidoscopic series of moderately random images. Hell; I can sometimes do a rather remarkable impression of Dory within the fractured remains of my conscious memory.
At any rate, though I'd long forgotten it, I'd bought the base game a long time ago - back before a couple of events and hospitalizations in reference to the preceding paragraph. At the time, I used a Yahoo E-mail account which worked fine, right up to the point that the phone it was connected to got damaged. Trying to get a
new phone attached to my account became a truly Orwellian runaround worthy of...well...Yahoo. (Or Poe. "For the love of God, Montressor! The phone is bloody GONE!!!"

) All I needed to do was use the authentication code sent to my old phone. Alternate E-mail? Well - totally my fault of course, though in my defense I
was rather busy with other things at the time (see earlier paragraphs) and hadn't thought to set one up. I
could do so now. All I needed to do was input the authentication code sent...well, you can guess the rest.
In three years I
never once managed to get through to customer service. Yahoo again. Eventually I gave up and started using Gmail. After a year of inactivity that old E-mail was wiped - one of the things I learned in my phone call this morning. (Apparently this number I called was a paid service - so in addition to not being able to do anything unless I was a paid subscriber of Yahoo, the rep let me know their assistance would be FAR more complete if I considered one of many plans and packages...)
All this is a
vague memory - since in my personal history we're coming up to another of one of what I rather dryly refer to as "my little moments", things got rather confusing for a time. At any rate, as far as I can figure, when I got back to ED after a rather circuitous series of events, they had Horizons. I got THAT, it's been on my current Frontier account and whatever happened in the past sank back into the rather sparkly Pensieve I nowadays have as memory.
...or something that's at least a rough approximation of that anyway.
At any rate - the upshot is that when FD Support sent the E-mail this morning, the reminder of that old account hit me like a ton of bricks, bringing back most of which I just wrote above. I sent a reply to them via the same E-mail, but I've no idea if that will be received. I'll wait a bit to see if I get a response, and if not I'll submit another ticket explaining the situation. (
Edit: I just found the little button that asks if my problem has been solved - allowing me to reopen the ticket. Which is what I'm doing now.) Since they
do have both of my accounts on file and know for certain they're both me (if nothing else they both share my mellifluous writing style

) - he referred specifically to both - I don't doubt they'll be able to migrate the account. I hope. It's been a couple of hours and I've gone from upset to merely annoyed. Give it a couple of days and I'll start to consider the delights of starting over, if that's what I have to do.
(Of course, as soon as I
do think that I'll promptly begin whacking myself about the head and shoulders with a baseball bat - if I
do have to start over that is going to be absolutely freaking awful.)
Cheers!