Oh no. More bad news. Where did you find out that these manufacturers discontinued their ballasts? I really hope Advance didn't discontinue their ballasts. AEL uses Advance ballasts so if they discontinued theirs then I don't know what AEL is going to use then.
A lighting seller based in Markham, called Canadalite, where I usually buy my stuff from if I cant find it online, He was only able to send me some left over symban ballasts, when I had ordered Venture. When I asked about Advance, he said they are all discontinued and they have non left in stock. Said it was all wattages when I asked. I don't know if its actually true but thats what they said to me.
so for now Im stuck with some symban ballasts with integrated ignitors and NPF, which will be great for spares but not what I want in my lights. Im currently hunting around online for leads on the 35 ballasts and 70w ones. Looks like I'll be going a bit over my budget that was set for this, but I need to get these things in before winter when covid hits again