It's NEVER too late to start! :P
That's why we leave all the block selections permanently posted. You can pick and choose which to do and do them whenever the mood strikes. ;-)
(don't tell anybody but i still have one or two left from 2007 and most of the 2008 blocks undone ... and i've been "in" since the very first one! :shock: :lol: :lol: :lol: )