In any case, one person on the list pointed out these instructions for Palm Sunday on page 273 of the prayer book:
The Passion Gospel may be read or chanted by lay persons. Specific roles may be assigned to different persons, the congregation taking the part of the crowd.Of course, I should point out that “may” occurs three times in these instructions; the suggestions are clearly only suggestions.
The congregation may be seated for the first part of the Passion. At the verse which mentions the arrival at Golgotha (Matthew 27:33, Mark 15:22, Luke 23:33) all stand.