LBV is the impatient drinker's vintage port - it is a vintage port, as in being from a single year and not blended across years. However, unlike actual vintage port, LBV (late-bottled vintage) is aged in wood for several years and then bottled as a ready-to-drink port.
Vintage port, by contrast, goes straight into bottle and generally requires years, if not decades, of quiet maturing (and often a lot of decanting to remove sediment) before being ready to drink.
LBV has the plumpness and primary fruit of youth, the richness and sweetness of port and if it is not as complex as a vintage port, it is a step-up from a basic ruby.
I'm generally not a fan of Laithwaite's wines, but I found myself appreciating this; you can probably get better ports for less elsewhere, but there is no reason to avoid this one. It has an IWSC Bronze medal, which roughly translates as "perfectly fine with no rough edges, but nothing really special".
Andresen LBV port 2011 (£16.99, Laithwaite's) sweet, ripe red and black cherry fruit, dark plum and cassis, oaky vanilla spice, eucalytpus and warming alcohol. Full, concentrated and expressive; fresh with very fine tannins.
Drink as a digestif; match with dark chocolate, mince pies or Christmas pudding.