My view would be, and this is the view of many Reformed leaning Anglicans, the Lord's supper with grape juice rather then wine would be valid but irregular.

Likewise theLord's supper with leavened bread rather then unleavened would be valid but irregular.

It would also be interesting to know how many congregations use a common cup and how many use individual cups.

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Thomas Yeutter,
Mason, MI
Member St. Patrick's Anglican Church, Comstock, MI

Ezra 7:10 For Ezra had set his heart to study the law of the Lord and to do it and to teach its statues in Isreal.