Direct quote from the rule:
[[[Any time the score differential reaches thirty-five points or more, the following changes will be made regarding rules determining when the clock will be stopped and/or started. In addition, in keeping with the rules that allow for mutual agreement between coaches for period shortening, the running clock may be implemented at any time by mutual agreement of the coaches.
Coaches choice may not supersede the automatic provisions with a 35 point differential
1. Once the running clock provisions are implemented, the clock shall continue to run from the point that the
differential occurs (and shall not return to official time) with the following clarifications: ]]]
then there are provisions such as player injury, administering fouls, heat time outs, etc. Note that the rule directly from the Director of Officials states “shall not return to official time” - nor does it state a half or anything else.