Bought a Unit, it transformed into another Unit.

There I was, one Yordle away from completing my Yordle comp. The game shone it's lights on me and showed me a Gnar in my shop, "Thank the heavens!" I thought to myself.

I go to buy the Gnar and lo and behold, it turns into a Volibear, the very same unit that was to the right of it in the shop. "But how can this be?" I go and check my shop once more, I probably made a mistake, but no, Gnar is no longer there and Volibear is also still in the shop. I test it out further, I buy the Volibear, it turns into a Zed, the unit which was on the far right. Still curious, and surprised, I tried to buy the Zed in the shop. Unfortunately, I couldn't buy him.

Quite flabbergasted, as you can imagine. However, I don't blame Riot Games, they are still an up and coming small Indie company. It's also my fault, if only my brain realized, the units which I bought in the shop transformed to the unit directly to the right of them, I should've bought whoever was left of Gnar. Because this was clearly a mechanic that was implemented during my ranked game