Mellotronists

Hello all,
I have what may appear to be an odd question, but I was wondering if 
anyone here has noticed  certain times of year when trons become more 
readily available on the market?  I ask because I've noticed over the 
last nine years or so on ebay that rarer, high-ticket items tend to go 
up for sale during what we in the US often refer to as Tax Season - or 
as I like to think of it, the time of year when I'm scrambling to raise 
funds to pay my taxes which I have again somehow managed to 
undercalculate.   If there is such a season for trons, I want to be 
ready with funding solidly in place (this year I managed to not owe on 
taxes for once).  Any info, tips, secret knowledge, jokes and/or insults 
about my intelligence, character, breeding, etc. will be greatly 
appreciated.

best,
john b