I have the 2710 with FL (401) and the 63" front mounted snowblower (can't remember the number). All of these are Kubota. There is a sub-frame associated with the FL and the SB. They do not interfere with each other. However, the SB sub-frame does require that the "nose mount" part of the frame for the mid-mount mower be removed (takes about 15 minutes and I doubt you will be needing the mower while needing the SB!). The SB sub-frame is very heavy but relatively easy to mount once you know how it goes (maybe an hour). The SB sub-frame is hydraulically actuated for up and down movement of the SB (so you are not always dragging the SB over the ground). The action is controlled via the FL valve (make sure you get the correct one when getting the FL). The SB sub-frame does stick out in the front beyond the tractor about a foot when the SB is not mounted (you just can't get as close to things as you would otherwise) and ground clearance is reduced. As I said, the SB sub-frame does not interfere with FL operation.
Now, to answer your original question - it takes me about 5 minutes to demount the FL and about 5 minutes to mount the SB. The mounting of the SB requires you to drive the SB sub-frame mount (male) into a socket (female) on the SB, flip the retain latch, attach the safety clip, connect the hoses (2), and connect the mid PTO drive shaft. Alignment may cause you to take a few minutes more, but, with practice, you should be able to do it in a few minutes. Come summer time, off goes the SB sub-frame and back on goes the mower sub-frame. Works real good! I got the 63" model because it covers the width of my R4s and then some.
I had a
B1750 for about 10 years and moved snow with the FL and rear blade. I spent a lot of time twisted around on the tractor while using the blade. I didn't care for it. The availability of a front mounted SB on the 2710 was one (!) rationale for upgrading (the 1750 was a great tractor). The front mounted SB can utilize the float function, and it works great! There is also a crank that comes back to the driver's position for adjusting the direction of the snow throw (not the angle, that is manually set). There are options for hydraulically or electrically repostioning the throw, but for $800, I can do it manually!
I have thrown dry and wet snow. No matter, it flies. Maximum snow depth has been around 10" (I have only had it about a season and it wasn't much of a season). However, I did try it out on a snow bank about 3' high and the SB didn't much care - just had to go slowly.
As you can probably tell, I like my snowblower! The combination works extremely well with the 2710. Oh, yes, the there are other attachments you can put on the sub-frame if you like (rotating brush, for example).
Cost for the snowblower and sub-frame is around $3000, which is more than you will pay for a rear mounted unit. Your choice.
I hope this helps.
Bob.