Here's the overall procedure I've settled into over the last 2 decades for my Holiday brew:
I typically brew my Christmas Old/Burton Ale sometime between January and March (average ABV varies slightly from year to year, usually anywhere from 8.5% to 10%). When the primary ferment is done, I add a percentage of beer saved from last year's brew (which in turn has a percentage of the previous year's brew, etc., etc., going back to the early/mid '90s)...the resulting blend is then bulk aged on a conservative amount of oak beans until mid November, at which time I introduce moderate carbonation in kegs. It then lives in the fridge until the first or second week of December when I finally bottle it (saving off a percentage for the next year's brew).
I have dry hopped it a few times, but ultimately found that I much prefer this particular brew without dry hopping, since it ruins the beautifully deep malt character (and technically, it seems that Old Ale/Burton Ale is more authentically traditional without the dry hopping anyway).
The beer going into bottle will already be carbonated, so no further conditioning is required and the resulting finished product is ready for immediate consumption ...OR the bottles can be laid down for a year or more. It is bottled very carefully so it holds up very well.
I started the tradition in 1991 and despite an erratic work schedule and a few tours with various stage productions, have managed to keep it going. This year will be batch 42/22...the first number representing the number of years I've been a home brewer, the second being the batch number for my little 'tradition'.
I generally keep about half for my own use to enjoy sipping in the winter months (after drawing off the required reserve for next year), and I give the rest as gifts to a select group of folks on my holiday gift list.