In general there is no limit on the installed length of flexible wiring methods except for Flexible Metallic Tubing (Article 360) and types A and C of Liquidtight flexible nonmetallic conduit (Article 356). The other flexible wiring methods can be installed in unlimited lengths, subject to the 360° between pull points and the support rules for the raceway involved. Remember that in counting the degrees, every little variation from straight counts, and this will provide a limitation on the installed length.
Don