I thought I was crazy when I noticed this the other day. I have faithfully been adding my extra 50 a month (even though I am no where close to running out of space).
It took a few clicks to realize what was happening. I've had it in the past where I clicked the link and nothing happened. It refused to give me my extra 50 until I had clicked it like 20 times. So this time when I clicked it and the link didn't go away I thought that was happening again. It wasn't until I really started looking that I realized it was actually adding the space after each click.
Now I've been waiting for the hammer to fall and for them to take back all that space. But it's still there.