I don?t know if it is true that the bees can maintain more warmth in winter (you don`t have a winter, anyways). I always thought so, too, but didn`t squeeze them too much in winter due to food reasons. So thereusually was a frame or even two without bees if it was cold.
Insulation of the ball-shaped cluster is good, surface minimal. If you squeeze them, they are in a prolonged cube, like a box. Surface is larger. So heat-loss is even more, mathematically. To minimize the disadvantages, some beeks in Germany use insulated follower boards, walls and insulated coverings.
This winter I didn`t squeeze them with follower boards. Reason being a "cement honey" and pine honey in the combs. With cement, they cannot use it in winter. Pine honey, too much fibre or something pressing on the bladder. So I wanted to make sure they could easily access all the feed they wanted.
Bees came out of winter just fine. Better than the last years, really.
In Your case i presume the bees breed all winter long. And every few days at least they will be able to access the feed "behind" the follower board. So as long as you have a surplus of bees "inside" the follower board (packed with bees), they should be fine with follower boards. And maybe better off, even. But for me - a long time believer in squeezing bees - it is a "maybe" still.
Follower boards in my (present) opinion are more or less only a means for the beek to control and steer the doings of the bees. Esp. concerning building comb and comb-hygiene (being able to remove old comb). And of course: Squeezing the honey up thru the excluder...