Hello,
Yes there is a training backlog at EVERY ARTCC. Some are longer than others, The best way to find out before you transfer is to email the Training Administrator for the ARTCC as they can give you the best information for that.
I can tell you at ZDV we don't necessarily have a long backlog, as students book when they can, but it takes about 5-6 sessions to complete your S1 training. So part of it is up to your availability as well.
I don't think this is going be something that will be advertised on webpages or the VATUSA page, but like i said, if you have an questions the TA is the best person to ask.
You also have to understand that every training staff is made up of volunteers and some ARTCCs training staffs are not as large as others. ZNY and ZLA training staffs don't match the size of ZDV or ZLC, so wait times will vary from ARTCC to ARTCC. We do what we can but we also have IRL things to take care of, as well as wanting to control ourselves.
V/r,
Mike Bencivenga
vZDV/vZLC Training Administrator