It's good advice to do it early but just FYI, you often can't get a new FEC any earlier than 30 days before the expiry of the current one - the same goes for the Residence Permit. In many places now though, the PSB are asking for you to submit your RP for renewal or transfer north of a week in advance of its expiry, so it can be a little tight.
The medical, in most places, needs to have six months validity left on it, so you can do that bit a few months early.