So after yesterday's frustrations, this afternoon was a success! I finished stitching together the extension strips and joined them to my backing material, so now it should be as wide as the quilt top (though this remains to be tested!)
As you can see, Maggie cat was a great help!
In the photos you might be able to see the first long strip of extension fabric attached to the far side of the backing sheet.
I have to say I'm finding these strips of fabric fiddly! And these are 2.5" wide... the thought of making a quilt out of a jelly roll of 1.5 to 2" strips sounds horrendous!! I think I'll stick to squares and just use strips as borders! ( my next quilt has those - strips on 2 sides of the squares!)
Maggie cat is going to be a terror when it comes to taping and spraying the various layers, which is the next step!