I remember my DCXL grew just like that when I was living in the Northeast, and I believe it has mostly to do with the length of day, and intensity of the sun. They made super long traps just like yours.
Now down in Hawaii, they initially went to making summer traps, but now all of them are right back to producing winter traps right in the middle of the summer where temperatures are already usually 85F-71F.
The rate of size increase is quite impressive though.
April 14th
May 5th
June 23rd- this picture was taken from the opposite side as the one that flowered is the biggest which now has 2 growth points