I've checked back through the blog (quickly), and couldn't find them, however - and they didn't seem to already be uploaded to the site when I checked on the resources page, so I thought it wouldn't hurt to put them up again (or for the first time - I definitely have 'back to school' brain...there are so many things to do, I can't remember any of them unless I write them down).
The AI phoneme is first taught at the end of Stage 1 (often Primary 1), then it is reviewed in the first few weeks of Stage 2. The AY phoneme is the first phoneme taught in Stage 2, after all of the Stage 1 phonemes have been reviewed. It seemed to make sense to put them together, though. I know that I taught my P1s the 'AY' phoneme last year - they were writing it every day when they wrote the name of each weekday along with their date, so most of them picked it up quite quickly. Get these cards by clicking either the picture above or here.