Get use to it. This is the con of having all these free accounts coming online.
After purchasing and playing the game for two months after launch(when it wasn't free) and after coming back for about a week now, in that time I can honestly say that I've either had to wait thru constant downtime or have been booted NUMEROUS times because of them taking the server down for whatever reasons. In any other mmorpg I have played, f2p or not, I haven't had this experience. Just my observation of what I've witnessed here compared to other games I have played, Your experience may differ.
That being said, I like what they've done with the game since Beta\launch, hate the constant downtime.