Treasury Regulations (26 C.F.R.)
26 CFR § 1.673(d)-1 — (d)-1 Postponement of date specified for reacquisition.
Any postponement of the date specified for the reacquisition of possession or enjoyment of any reversionary interest is considered a new transfer in trust commencing with the date on which the postponement is effected and terminating with the date prescribed by the postponement. However, the grantor will not be treated as the owner of any portion of a trust for any taxable year by reason of the foregoing sentence if he would not be so treated in the absence of any postponement. The rules contained in this section may be illustrated by the following example:
Source: official text