Absolutely correct. Tracks are agreed in the morning by Oceanic Controllers at Shannon, avoiding the stong westerly jetstreams which move from day to day and season to season.
In the evening Gander organise the eastbound track system, but in this case attempting to take advantage of the strong easterly winds to reduce flight times to Europe.
Often an actual ground distance many hundreds of miles further than the shortest track will result in a shorter flight time due to these strong winds.
I have operated flights from the UK to Florida on tracks ranging from about 51 North to 59 North, just to avoid the jetstream wherever it may be on the day. In fact the quickest (ground) distance on such a route would be following a track along about the 52 degree latitides.
Similarly on the way home have gone up to about 59 North to catch tailwinds winds of up to 200 mph. Bumpy ride through the night sometimes I can tell you.
I used to love the smell of Jet-A in the morning...