.
...oh yeah, one final thing. Try to do some research and find out whether your aluminum bicycle frame was heat treated after it was welded together.

The better ones, with thinner walled tubing all are, but I don't really know what it is you have there. And it's entirely possible that if it's manufactured out of thicker walled tubing, and weight was not so much an issue, that yours might not have been. Again, I just do not know with your particular bicycle.

But if it's not been heat treated, just TIG or MIG welded together in some Asian sweatshop as a utility bike at a certain price point, then if you do start to notice some cracks radiating out from your drilled holes in the stays, it's not a big job to get someone to fashion some aluminum sleeves to go around the stays, halve them so you can place them on the stays in the right spot, and use a wire feed or other gas shielded welder to reinforce and support the stays for three or four inches at the holes. It's fugly, but workable.