"[C]ritical and declining plans that need to implement benefit suspensions in order to remain solvent are able to take this action as soon as possible. Delays could lead to a necessity for larger benefit suspensions will be necessary in order for plans to survive.... [A] change in the effective date of the benefit suspensions will result in the notices overstating the impact of the suspensions submitted for Treasury approval due to benefits becoming eligible for additional protection under the age limitations. Guidance does not need to require the production of revised individualized estimates. However, advance notice to pay status participants alerting them to their actual benefit change would be appropriate shortly before the final implementation date."