I would be tempted to do it now and take advantage of the tree being bare rooted and somewhat soft now.

Just be very careful pulling them down. They can feel soft, but still have a breaking point. The String method that Martin used is best rather than wire. Can always tighten the strings a bit later.

Not sure how well using Fabric pots are going to work for the string method. Have seen Jericson do it, but you lose a lot of support given by a rigid pot as opposed to a fabric one.

Rick

I'd go ahead and do it. Be careful, but they'll tolerate more bending than you might expect.

If you want them to bend further but aren't sure if you can push it, just leave it bent as far as you feel combortable. You can wire it as it grows out and still get the same effect.