Club e-mails before going away

Can anyone explain the system regarding the e-mails the Club sends out, usually a month before going to a site.

I only ask as I received one hoping I enjoy my holiday at Chapel Lane for one night (it's a stopover!). I have subsequently received another e-mail, also for Chapel Lane for 2 nights at the end of April. After our first stop at Chapel Lane we're moving on to Cheddar for 4 nights but this has not warranted an e-mail. Does this mean that the Club do not want me to enjoy my stay at Cheddar or should I look for another site !!

Only joking - I just want to know what the system is.